In 974 CE, the Chinese emperor Taizu of Song held a naval review in which hundreds of warships fought a mock battle. His fleet consisted of galleys called ‘sea hawks’, which were armed with catapults and reinforced with iron, and junks equipped with landing gear.1 In the following century, the Song emperors built the most powerful navy in the world. It contained 13,500 ships, engaged rivals with explosives, launched major expeditions to Vietnam and around the Korean Peninsula, maintained a base in the Philippines, and had the knowledge to navigate all the way to the Strait of Hormuz.² This naval prowess was backed by an immense domestic economy and industrial capability, and by a clear imperial vision of using that might against barbarians or pirates or whenever Chinese interests beyond its borders were threatened.³

If there seemed one power ready to spread its influence globally at the dawn of the second millennium, therefore, it was China. But it was not to be. Song China was far from united and so its naval power ended up being deployed mainly on rivers to quell domestic unrest. What held China back the most were invasions of barbarians in the north: first the Jurchen in the twelfth century and then the Mongols in the thirteenth.

The Mongol attacks halted China’s economic growth and it would not recover until the Ming Dynasty over 150 years later.4 This was a turning point which decisively altered the balance of power in the Eastern Hemisphere. Although the Mongols also struck at the Islamic powers and the kingdoms of Eastern Europe, they did not advance further west than Vienna, unlike the Huns before them. If they had, then the development of Western Europe at this time – the agricultural innovations, the expanding trade, the rise of cities as commercial centres, the construction of kingdoms – might have been completely annulled.

It is not known exactly why the Mongols aborted their campaigns in the West, but it seems to have been more a question of geography – and a stroke of luck – than a European military triumph. No longer at risk of imminent annihilation by external aggressors, Europe’s polities devoted themselves to an ever more relentless contest for military, economic, and financial primacy. It involved not just kingdoms, principalities, and duchies, but also increasingly powerful and self-confident city states, of which Venice was the prime exemplar. Ambition and aggression, however, also spilled over into other arenas. But even the sacred war against the occupation of the Holy Land – the most notable of the various Crusades against unbelievers – involved only a few thousand knights at any one time. Such armies were accompanied by large throngs of both fortune seekers and the faithful, and were notorious for their equally deficient logistics and leadership. This was not yet the era of Europe’s spectacular global conquests.

The Song

Following the Battle of Gaoping in 954 – which halted the nomadic forces in the north of China and allowed the south to be unified – the Song Dynasty announced in 960 that it had received the mandate of heaven. In accordance with the Confucian teachings, the first Song emperor, Taizu (960–76), promised to restore harmony, reassuring his subjects that: ‘We model ourselves on the unselfishness of Heaven and earth.’5 In reality, the first century of the Song Dynasty was characterized by a long struggle to overcome those states, and individuals, that still refused to accept their supremacy.

Taizu began the task of consolidating his power by building an army of hundreds of thousands of soldiers. Enemy warlords were given a stark choice: face overwhelming force, or accept a lifetime of retirement on some secluded country estate far from the centres of power. Loyal generals, however, were rewarded with provincial governorships. Civilian government was placed on a firmer footing, in the course of which it was reorganized into three distinct departments: a central secretariat; an advisory chancellery; and a department of state affairs, which itself consisted of ministries of personnel, finance, war, justice, public works, and rites. The last of these ministries oversaw foreign relations, court ceremonial, the civil service exams, and Buddhist and Taoist priests. All government functionaries had to swear subservience to the emperor, not to loot the countryside, and not to abuse civilians.

As domestic unification advanced, the main security question became how to defend the border against the major states to the north: the Liao, and the kingdom of Xia, a Tibetan people. In 1005, the Treaty of Shanyuan was sealed with the Liao. It stipulated that the two powers mutually recognize each other as equals; but the Liao regarded the Song’s annual ‘gift’ of silk and silver as tribute. Some time later, the Song court debated how best to deal with border raids by the Xia. Some favoured maintaining the existing policy of conciliation, albeit on pragmatic grounds.6 ‘Our generals are mediocre; our soldiers are not sharp,’ one advisor said. ‘We should wait until they are internally divided, and then launch a major attack.’⁷

Others argued against appeasement. A belligerent faction of officials cited the example of the Treaty of Shanyuan, referring to it as a humiliation. By effectively yielding the north to the Liao, they averred, the Song would never become as mighty as the Han or the Tang. ‘Our soldiers are growing older, while the enemies are getting stronger day by day,’ added another.⁸ ‘We have been in peace for too long. People do not know how to fight and are easily frightened,’ asserted the statesman Fan Zhongyan. ‘The Xia people dare to be our enemy because they have already secured help from our great enemy, the Liao’, posited another official.⁹ But, in the end, the emperor decided to negotiate a deal and once again buy peace with ‘gifts’ of tea, silver, and silk. ‘We shall secure a century of peaceful relations,’ he promised.¹⁰

What followed was indeed a period of prosperity. The Song emperors strengthened their control over both the North China Plain and the rich agricultural region south of the River Yangtze. Under Emperor Shenzong (1067–85), the so-called New Policies introduced a primitive form of welfare state. They included the redistribution of food, price controls, pensions, care for orphans, and the end of forced labour. Living conditions improved. Economic production per capita might even have doubled during this period, due to the re-establishment of peace, the introduction of more productive rice variants from Southeast Asia, and the rapid development of industries including iron and silk. Both internal and external trade flourished. In 1087, a new trade office was established in the southeastern city of Quanzhou, which became the chief entrepôt for China’s foreign maritime commerce.

Song China became the world’s largest economy, exercising a huge power of attraction over even hostile states. The neighbouring Liao rulers, for example, did everything in their might to emulate the opulence and refinement of the Song. The military balance shifted as well. Between 979 and 1041, the Song army trebled in size to 1.25 million men. The Song mastered the manufacture of gunpowder and introduced catapults with explosive bombs. They imposed an export ban on sulphur and saltpetre which, along with charcoal, formed the key ingredients of gunpowder. The emperor also ordered a breeding programme to reduce the Song army’s dependence on horses imported from Central Asia. Alongside their military power, the Song resorted to economic coercion and cut off trade with neighbours if they refused to submit.

The era of tranquillity did not last. China’s army may have been large and well-equipped, but it was never able to subdue the Song’s foreign enemies. The peace treaty with the Xia failed to demarcate the border and so clashes continued.11 In the south, the Song allied with the Champa to try to subdue the Ly Dynasty in Vietnam. The war sapped the imperial army’s strength until, in 1077, it was forced to withdraw. Such campaigns, and the annual ‘gifts’ to the Xia and the Liao, drained the treasury. ‘Eighty or ninety percent of our treasury income went to the military. Our troops can be said to be many. Our treasury can be said to be exhausted,’ worried a senior imperial official.12 The situation was worsened by the famine that ravaged northern China in 1074–6.

Setbacks now followed each other rapidly. Emperor Zhezong, who took the throne in 1085 when he was only eight, opted for a confrontational policy towards the Xia. His successor in 1100, Emperor Huizong, allegedly neglected his responsibilities in order to pursue his love of the arts. In 1125, as the emperor blissfully dabbled in poetry and painting, the Jurchen rebelled against their Liao overlords. Although Huizong chose to support the Jurchen in overthrowing the Liao, after their victory the Jurchen turned against the Song and launched a surprise attack on their capital. Faced with this invasion, Huizong abdicated in favour of his son. In 1127, both the new emperor and his father were captured and taken back to the Jurchen capital in Manchuria.

The speed and scale of the Jurchen triumph can be attributed to a combination of Song complacency and incompetence, and the fact that the Song’s advantages in infantry, artillery, and warships were outweighed by the Jurchen’s superior cavalry. The Jurchen ‘were victorious only because they used iron-shielded cavalry, while we opposed them with foot soldiers’, a Song general later explained.¹³ The Jurchen Dynasty, called Jin, consolidated its rule over the northern plain, while the remnants of the Song retreated to the Yangtze where they continued to rule in the guise of the Southern Song Dynasty. In 1141, the two negotiated an agreement that fixed the border between them, in return for which the Southern Song agreed to pay a large annual tribute in silver and silk. For a while, both empires flourished. Thwarted in the north, the Song were ready to channel their energy overseas. The navy was again expanded, new ports opened, and maritime exploration was encouraged.

It was almost precisely at this point that the Mongol threat emerged. The Mongols dwelt around the Orkhon Valley in Mongolia, the same area where the Xiongnu had lived centuries before. In 1130, the Khamag Mongol confederation first clashed with the Jin. When a treaty was signed in 1147, the Mongols compelled the Jin to pay tribute. The peace was short-lived; and in the new skirmishes that followed, the Mongols were pushed back. But a series of exceptionally cold summers decimated the Mongol herds, causing them to reintensify their efforts to advance south. In 1206, the Mongol tribes coalesced around one of the most legendary leaders in history, Genghis Khan, his name meaning ‘universal ruler’. The khan propagated the idea of a holy war, ordered by the sky god Tengri, to unify the world under Mongol rule and avenge maltreatment from the past.

The Mongol force that attacked China in 1207 was probably no more than 150,000 strong, and entirely mounted on small but sturdy horses. It nevertheless made in-roads, thanks primarily to the Mongols’ tactic of lightning charges, their lethal composite bows, their readiness to sacrifice thousands of men in order to seize strategic passes, and the defection of Jin generals. By 1234, the Jin Dynasty had been terminated, its death blow delivered by a combined Mongol–Southern Song army. ‘Corpses sprawled, curled up beside the road – hordes of half-dead prisoners,’ lamented the Jin poet Yuan Haowen. ‘Our spirit’s broken.’14 The Jin’s territory almost immediately became a launch pad for Mongol attacks against the Song.

The Southern Song offered intense resistance. Over the course of a war that lasted decades, the Mongols slowly won control of the devastated border provinces; as they became familiar with the Song’s gunpowder weapons and siege engines, they increasingly used them against their inventors. In 1276, the Mongols finally took the Song capital, Lin’an (Hangzhou). ‘The ruling senior ministers forgot their enmity and submitted to humiliation,’ the invaders’ chronicles boasted.¹⁵ The carnage caused by the Mongol invasions was immense: tens of millions of people were killed. It would take almost three centuries for the population and agricultural output of China to recover.¹⁶ Of equal geopolitical significance in the long term was the fact that the great upsurge of Chinese cosmopolitanism under the Song – one of the most outward-looking of Chinese dynasties – had been cut off at the roots.

Subduing Pagans into the Service of Christ

In some ways, the Mongols were merely the latest nomadic barbarian society from the fringes to take over the Chinese heartland. What made them different, however, was that they simultaneously entertained hopes of conquest as far as the Persian Gulf and the Mediterranean. The first Mongol campaigns back in the twelfth century may have been triggered by climate change and opportunism over the weakness of the Jin, but once the hordes started counting the spoils of their victories, they fell under the spell of Genghis Khan’s promise that he would lead them to even greater wealth and to the empire ordained for them by the sky god Tengri. The descendants of Genghis Khan left little to the imagination. His grandson, Güyük Khan, referred to himself as the ‘emperor of all men’ when he wrote to Pope Innocent IV in 1246.

From the rising of the sun to its setting, all the lands have been made subject to me. Who could do this contrary to the command of God? Now you should say with a sincere heart: ‘I will submit and serve you.’ Thou thyself, at the head of all the Princes, come at once to serve and wait upon us!17

The Mongol khans between them plotted to conquer Eurasia as far as the ‘great sea’, or Atlantic Ocean. Between 1237 and 1241, they devastated Eastern Europe, killing half of its population. The reports that reached other European cities were shocking. ‘They dragged men and women alike into the churches and shamefully mistreated and then killed them there,’ wrote the prelate Roger of Apulia from the kingdom of Hungary. ‘Their recreation was to rape the girls or wives before the fathers’ or husbands’ eyes.’¹⁸ But the Mongols disappeared from Europe as quickly as they came. Climatic change was probably at work again: increased rainfall made the steppes of Eastern Europe swampy, slowing down the Mongol cavalry and depriving them of fodder. The Mongol hordes in Europe were smaller than in China too – and lacked their siege engines – so that heavily fortified European cities could hold out for longer. Many commanders were called back to elect a new leader after the death of Genghis Khan’s successor, Ogodei. Western Europe had been spared from Mongol invasion. It remains an intriguing question as to what would have happened if the Mongols had not turned back.

In any case, the European political scene in the mid-thirteenth century remained fundamentally as disunited and multipolar as it had been when the sons of Charlemagne divided his empire between them 400 years earlier. By the early eleventh century, the six largest polities were the Holy Roman Empire – which dominated Europe from its geographic heart in Germany – the Byzantine Empire, and the kingdoms of France, England, Poland, and Hungary, although these bore only a limited resemblance to their later incarnations. None of them as yet possessed a strong centralized regime, or even well defined borders, but remained looser agglomerations of duchies, earldoms, autonomous cities, and even bishoprics. And there was also the papacy, whose position of spiritual authority imbued it with potentially tremendous political influence.

After the last Carolingian emperor of East Francia died without issue in 911, the leaders of the territories comprising what would become known as the Holy Roman Empire chose his successor in an election. For centuries thereafter, the emperor continued to be elected from candidates, all of whom belonged to the same successive, Germanic dynasties: the Ottonians, the Salians, the Hohenstaufen, and so on. It was the Ottonian emperors of the tenth century who first based their imperial authority on the principle of translatio imperii – namely, that there was a single imperial mandate, which had passed from the Romans to the Byzantines, from them to the Franks, and from them, in turn, to the Germans. Hence their assumption of the titles ‘king of the Germans’, ‘emperor of the Romans’, and the ancient honorific Imperator Augustus.19 Their Christian aura was burnished by propagandists like the historian and canoness Hrotsvit of Gandersheim, who portrayed Otto I as a new biblical King David, ‘subduing pagans into the service of Christ so that a stable peace for the holy church might be established’.²⁰

Christian peace, however, was the thinnest of disguises for the Ottonians’ profoundly worldly and expansionistic strategy. Their empire lacked restrictive natural borders. In the west, where it straddled the Rhine, possessions like Lorraine and the Low Countries brought it into conflict with France. In the south, the duchy of Bavaria bestrode the Alps so that the Brenner Pass giving access to Italy lay within it. In the open plains of the north and east, Ottonian troops fought ceaselessly with Denmark, Poland, and Hungary. The Ottonians were also not above exploiting the weakness of lesser monarchs to absorb their lands into their own realm. When Otto I intervened to free Queen Adelaide from imprisonment by the Lombards in 951, for example, he took the opportunity to have himself crowned king of Italy. Ten years later, when usurpers had seized the Italian throne in Otto’s absence, he answered the pope’s desperate plea that, for ‘the love of God … the king would free the pope himself and his ward, the Roman church, from the tyrants’ fangs, and return them to their original health and liberty’.²¹ ‘Considering not his own interests [and] having gathered his forces, Otto came quickly to Italy,’ piously intoned the Italian churchman Liudprand, who was rewarded for his Ottonian loyalty with a bishopric.22 Otto ensured that his reward was the pope’s formal acknowledgement of his imperial supremacy.

In the seven decades that followed, emperors promoted and deposed pontiffs at their pleasure. But gradually the papacy underwent a process of renewal that enabled it to claw back many of its former prerogatives and much of its standing – to the point where it was even able to excommunicate Emperor Henry IV in 1076, thereby provoking a rebellion within the empire. One of the fiercest areas of conflict between pope and emperor, however, remained the right to appoint bishops. Finally, a compromise was reached in 1122 at the Concordat of Worms, which recognized the emperor’s right to bestow bishops with secular authority and the pope’s to grant them their spiritual authority. But tensions between the papacy and the emperor, as well as with other secular rulers, continued to seethe throughout the Middle Ages, exacerbating the discord and instability that blighted so much of the politics of the era.

The German expansion was possible because the French kings struggled to ward off the Norse raiders. By the tenth century, some of these Norsemen had been allowed to settle in the northwest of France, where they gave their name to the region: Normandy. Others continued to pillage the coasts of Western Europe. From the Baltic, they sailed their longships up the European rivers to loot towns, farms, and monasteries. Later on, the French kings also became ensnared in conflicts with the powerful Angevin kings of England, who also controlled much of the western coast of France, and the many barons who hedged opportunistically between them. In 1190, King Philip II sealed an alliance with the English king, Richard the Lionheart, but the agreement broke down, and in 1214 the armies of the two countries met on a battlefield near Bouvines, in what is now northern France. The French were victorious and could finally enforce sovereignty over Normandy and Brittany. King Louis IX of France (1226–70) made important steps in centralizing power and gradually the balance of power started to shift. By 1250, Louis was in command of the most populous country of Europe, the largest economy and the largest army. He called himself le lieutenant de dieu sur terre, ‘the deputy of god on earth’.

This ushered in a period of relative stability for Europe, which would allow it to thrive again and, for the first time since the fall of the Roman Empire, wield influence far beyond its borders. There were growing hopes for a true Christian peace. From the monasteries, the churches, and the cities an embryonic pacifist movement emerged that advocated a ‘peace of God’ – or at least, a ‘truce of God’. Particularly prominent were monks from the influential French monastery of Cluny, who organized a series of peace gatherings. ‘No Christian should kill another Christian, for whoever kills a Christian undoubtedly sheds the blood of Christ.’23 Although, in time, even kings and emperors propagated the idea, wars among European Christians continued to be fought.

But a more important evolution during the period was the weakening of external threats to Europe as the Muslim world fragmented. This permitted a Christian pushback. In 1095, Pope Urban II launched a holy war to recapture Jerusalem: the First Crusade. Between 1095 and 1271, at least nine military expeditions left Europe with the purpose of campaigning in the Holy Land. The fact that the disorganization and confusion among the crusaders did not elicit an immediate counterattack, shows the political vulnerability of the Islamic world. After immense hardships, the warriors of the First Crusade captured Jerusalem in 1099 and ruled it for nearly a century. The God-given victory was accompanied by apocalyptic violence, as the crusader chaplain Raymond of Aguilers recorded: ‘Some of the pagans were mercifully beheaded, others pierced by arrows plunged from towers, and yet others, tortured for a long time, were burned to death in searing flames.’24 By the time the fighting ended, many thousands of Jerusalem’s Muslim and Jewish inhabitants had been massacred.

A warmer climate, the increased prevalence of iron tools, and the introduction of crop rotation allowed for the improved agricultural yields that fostered steady economic growth in this period. These so-called High Middle Ages were the first time since the heyday of the Roman Empire that agricultural surpluses were able to sustain the development of crafts and increasingly long-distance trade as well as the development of large cities. In recognition of their vital commercial role, cities began to receive, or to take for themselves, new liberties, which only incited further the competition for glory and prosperity. The era’s economic growth also led to population growth: by the thirteenth century, Europe’s population had reached 60 million, almost on a level with China, India, and the Middle East.²⁵ And population growth led in turn to migration. The overcrowding of cities and competition for land caused many young men from Western and Northern Europe to seek their fortunes on the Crusades – where religious and economic motives went hand in hand – and in the far wilder reaches of the continent’s east.

Beyond the Danube

If Hungary, Bulgaria, and Kievan Rus’ cushioned Western Europe from the Mongol invasions between 1237 and 1241, the resulting destruction and depopulation created a void from which German princes, the Teutonic Knights in the Baltic area, and many others benefited. But the region recovered, thanks partly to migration from Central Europe and growing trade along rivers like the Danube, Vistula, and Dnieper. Poland under the Piast Dynasty revived and became one of two main Catholic realms, along with the kingdom of Hungary. Hungary grew rich from its gold and salt reserves and from controlling much of the trade between the Holy Roman Empire, the Adriatic, and the Black Sea region. From the trading city of Novgorod had sprung the federation of Kievan Rus’, which after the Mongol attacks continued to prosper on the traffic between the Baltic and the Black Sea that was carried along the River Dnieper. This brought it into sustained contact with Constantinople, which led to its adoption of Orthodox Christianity in much the same way as had happened earlier with the Bulgarian Empire, near the Black Sea. These states were in permanent competition with each other, with neighbouring semi-nomadic peoples like the Cumans and the Pechenegs, and with the main power to their south: the Byzantine Empire.

At the beginning of the eleventh century, Constantinople was still the largest city of Europe, squatting like an enormous spider at the heart of a giant web of commerce that spanned much of Eurasia. Its vast walls had been besieged nine times, but it had never fallen. Its empire had experienced a revival in the tenth century. Churches and monasteries, austere on the outside, richly decorated with mosaics and wall paintings on the inside, were built wherever the Byzantines controlled the trade: in Calabria, Chios, the Peloponnese, Athens, Cyprus, and so on. A network of fortified ports near strategic gateways like the Bosporus, the Strait of Messina, the Strait of Otranto, and the delta of the Danube collected immense amounts of revenue. Trade treaties were signed with monarchs who supplied furs and metal from the north. Domination of the Black Sea grain trade was vital.26 To protect this commercial empire, the Byzantines deployed a large fleet of galleys, maintained a barrier of fortresses in Anatolia to guard its southern border, and sowed division among the states and peoples adjoining its northern frontier.

In his De Administrando Imperio, a work on imperial governance, the tenth-century Byzantine emperor Constantine VII had advised his son to show wisdom, to avoid relying on armed force, to foster the alliance with the Pechenegs against the Bulgars, the Kievan Rus’, and the Turks – and never to sell them the incendiary weapon known as ‘Greek fire’, on which Byzantine naval supremacy in particular depended.²⁷ But the empire’s security was challenged nevertheless: by an alliance between the Pechenegs and Bulgars; by the Normans, who took control of the Ionian Sea; by a civil war in 1047, which elicited an attack from the Pechenegs; by growing assertiveness from the Seljuk Turks in Anatolia, marked by their decisive defeat of the Byzantines at the Battle of Manzikert in 1071. ‘It was my misfortune to find the Empire surrounded on all sides by barbarians, with no defence worthy of consideration,’ said the Byzantine emperor Alexius I, according to his daughter, Anna Comnena.28

The new dynasty established by Alexius I Comnenus (1081–1118) eventually restored order, but at a very high price. Domestic unrest made the emperor neglect the navy, so that the Byzantines had to rely on the support of their former dependent and now up-and-coming economic rival, Venice. The Byzantine chronicler Niketas Choniates described how the lack of funds for the imperial navy strengthened the position of Venice, damaged trade, and diverted even more income from the treasury.²⁹ Protected by its shallow lagoon, the Venetian republic tried to isolate itself from the turmoil on the Italian Peninsula and turned to the sea. In 1082, in exchange for assisting the Byzantines in their attempts to resist the Norman encroachment into the Ionian Sea, the Venetians were granted the right to trade throughout the empire free from any taxes.

Under the Comnenian Dynasty, Constantinople flourished again for much of the twelfth century. It continued to look down on the Western Europeans, regarded the Orthodox Church as superior, and contented itself with the fact that the loss of its direct control of trade was compensated somewhat by the commercial activity that the merchants of Venice generated in Constantinople.³⁰ Yet continued military weakness forced the emperors to pursue alliances with the West. It was a Byzantine embassy at the Council of Piacenza in 1095 – informing Pope Urban II about the plight of Christians in the East and begging for aid – that led to the preaching of the First Crusade a few months later. Distrust between Constantinople and Western Europe, however, remained deep-seated. The Byzantines still thought of the Western Europeans as barbarians. Westerners returned the favour by regarding the Byzantines as lazy, overbearing, and deceitful.31

By the late twelfth century, the balance of maritime power in the Mediterranean had shifted decisively to the west. In 1180, Constantinople could only muster thirty vessels, Venice over a hundred. Meanwhile, distrust between the Byzantines and the West, coupled with Venetian mercantile and political ambitions, resulted in the sack of Constantinople in 1204 by a combined force of Venetians and troops from France and the Low Countries, who had come east to crusade in the Holy Land. To the horror of the Byzantines, a count from tiny Flanders was crowned emperor. The empire fragmented as territories refused to recognize the new ruler; what was left of the trade fell almost exclusively to Venice.

Destroyer of the Infidels

East of Constantinople, no major power was able to match the long-lasting success of the early Islamic caliphates or previous empires like the Sasanians’. In the eleventh century, the vast area between China and Europe remained fractured as four main powers competed for supremacy: the Ghaznavids, with their power base in what is now Afghanistan, the Buyids in Iran, the Seljuks in Anatolia, and the Fatimids in Egypt. Although the Abbasid Dynasty also survived – and their prestigious capital, Baghdad, remained an important centre of culture and learning – they fell under the effective control first of the Buyids and then the Seljuks, who turned them into puppet kings and burnished their own credentials by association with the lustre of the caliphate.

The Seljuks had originated as part of a band of Turkish tribes living on the plains between the Caspian and Aral Seas, where they had converted to Islam in around 950. In 1034, at which point they numbered no more than about 10,000 people, they were forced to leave their homes on an arduous migration: ‘From sheer necessity,’ recorded the thirteenth-century Syriac chronicler Bar Hebraeus, ‘they are compelled to depart to another quarter in order to find food for themselves and their beasts.’32 Initially, they hoped to obtain a new home peacefully in the region of Khorasan – now Iran and Afghanistan – writing humbly to the Ghaznavid sultan: ‘If the sultan sees fit, he will accept us as his servants … we have nowhere else to go.’ But the sultan’s vizier recommended caution: ‘Up to this point, this has been an affair of dealing with shepherds, now they have become armies who seize provinces.’³³ When the Ghaznavids sought to drive the Seljuks away, they were defeated. Forced to grant the Seljuks’ original demands, the Ghaznavids were powerless to stop them seizing the great caravan city of Merv as well in 1036.

But soon the Seljuks were no longer satisfied with what they held. In 1040, they defeated the Ghaznavid Empire, which by then was severely weakened by over-taxation and religious oppression. Its slow-moving troops were no match for the mobile Seljuk cavalry. In 1055, the struggling Abbasids called on the Seljuks’ assistance against the Buyids. The Seljuks promptly drove the Buyids out of Baghdad, and kept the city for themselves, albeit nominally under Abbasid suzerainty. In 1071, they decisively defeated the Byzantine army at the Battle of Manzikert, which gave them control over most of Anatolia. By this time, the Seljuks were claiming to be the descendants of the ancient Achaemenid kings of Persia and to have inherited the divine right of the Sasanian rulers. They also aspired to universal rule, as the roll-call of titles belonging to Kilij Arslan II, a descendant of the victor of Manzikert, illustrates:

The great sultan, the august shahanshah, chief of the sultans of the Arabs and the Persians, master of the nations, glory of the world and religion, pillar of Islam and the Muslims, glory of kings and sultans, defender of the law, destroyer of the infidels and the polytheists, helper of the fighters for faith, guardian of the countries of Allah, protector of the servants of Allah, sultan of the lands of Rum, Armenia, the Franks, and Syria.34

The conquest of Anatolia brought the Seljuks into direct confrontation with the Fatimid Dynasty in the Levant. The Fatimids were Shia and predominantly of Berber stock, having originated in what is now Tunisia. They had shifted their centre of power to Egypt in the late tenth century in furtherance of their primary objective, which was to oppose Sunni Arab expansion.³⁵ Their rulers were as much religious leaders as political ones: they claimed not only the title of caliph, but also that of imam, or leader of the Shia, and Mahdi – the saviour whom the Shia expected to restore justice just before the end of the world. ‘The world is yours and your dynasty’s,’ sang a Fatimid poet. ‘Young is your empire, O Mahdi, and the time is its slave.’36 From Egypt, the soldiers of the Fatimids marched in the footsteps of the ancient pharaohs’ armies across the Sinai Desert, into the Levant, and even on towards Mesopotamia. But after failing to overcome Abbasid resistance, the Fatimids then found themselves being driven back by the Seljuk advance out of Anatolia.

By 1076, the Seljuks had captured Damascus and were forcing their way deep into Egypt. A Jewish trader in Cairo was left dumbfounded: ‘They entered Fustat [Cairo], robbed, murdered and ravished and pillaged the storehouses.’³⁷ The early thirteenth-century Arab historian Ibn al-Athir recounted: ‘Wars between the rival sultans went on and on, corruption spread, possessions were plundered, blood was shed, the land was ruined, the villages were burned.’³⁸ Faced with the Seljuk threat, the Fatimids took advantage of the presence of the First Crusade, which had advanced through Anatolia and was inching towards Jerusalem. In 1098, the Fatimids proposed partitioning the Levant: Syria would go to the Franks and Palestine to them. The proposal fell on deaf ears, but by this time the danger posed by the Seljuks seemed less imminent. A succession conflict had split the Seljuk realm in two, with the sultanate of Rum in Anatolia and the Khwarazmian kingdom in Central Asia.

The Fatimids too fell prey to internal struggles, their authority having been weakened by their conflicts with Seljuks, crusaders, and North African tribes, and by the growing power of wealthy landowners. Finally, in 1171, an ambitious vizier named Saladin toppled the Fatimids and founded his own Ayyubid Dynasty in Egypt. Saladin pushed the Seljuk sultanate of Rum back to Anatolia and reconquered Jerusalem from the crusaders. Although a new crusader army led by Richard the Lionheart subsequently delivered a decisive defeat to Saladin at the Battle of Arsuf, it failed in its objective of taking back Jerusalem. By the time Saladin died eighteen months later, in 1193, Richard had abandoned the Holy Land, fearing attempts on his throne in England. It was left to the Mongols to deliver the fatal blow to the Islamic polities. In 1258, they sacked Baghdad, casting the Muslim world into disarray.

‘The sultans were at loggerheads with each other,’ wrote Ibn al-Athir about the Islamic Middle East in the late eleventh century. ‘This enabled the Franks to occupy the country.’39 After the fracturing of the Abbasid Caliphate in the ninth century, no single Islamic power was able to control Egypt, the Levant, Mesopotamia, and Persia at the same time. The irrigation systems in Egypt and Mesopotamia were neglected as elites focused on trade instead. But, protected by its Adriatic lagoon, Venice slowly undermined Islamic commercial dominance in the Eastern Mediterranean. Only under powerful Ottoman sultans like Selim I and Suleiman the Magnificent in the sixteenth century would the Islamic world regain a degree of unity.

The Gates of Hind

At first glance, the period from the eleventh to the mid-thirteenth century in the Indian subcontinent was an age of spectacular art and architecture, science and literature – at least for the large elite whose enviable lifestyle was supported by an immense economy. Ships traded with far-flung places, returning with rich and exotic goods. There were powerful merchants’ guilds, thriving and tax-free trade villages, and royal agents to safeguard commerce across the border.40 ‘Gardens, filled for the enjoyment of all mankind with grapes, lecture-halls, wells with pellucid water and drinking fountains’ – these were what distinguished India from the arid, dusty towns of Central Asia.⁴¹

Yet this was also an era in which over a dozen kingdoms struggled for supremacy. Many literary works describe a world rent by divisions and discord, a realm of spies, shifting alliances, overambitious kings, and fratricide. ‘Royalty is a thorny creeper; it destroys family affection,’ stated the king of a small realm in Kashmir.⁴² Class struggle between the rich and poor castes of Hindu society was rife, and resentment against the ruling class widespread. ‘Crabs kill their fathers, small bees their mothers, but the ungrateful Kayasthas, when they become rich, kill all,’ observed the same Kashmiri king. The trader, he continued, ‘differs from the tiger only in having a face smoothed with oil, in his power of speech, and his humble mien … Prostitutes, Kayasthas and big merchants are naturally deceitful. Men’s energy, like that of sleeping serpents, is not known till they are angry.’⁴³

During this period, the Hindu Chola kingdom in southeastern India emerged as one of Asia’s most powerful trading nations. The Cholas invested heavily in irrigation systems to increase agricultural production, but also maintained a fleet of hundreds of vessels, which they deployed for trade as well as military expeditions. In the final years of the tenth century, they invaded Sri Lanka, having learned of internal strife on the island from a merchant. The Cholas turned Sri Lanka into a quasi-colony, destroying Buddhist monasteries, incorporating local chiefs, clearing forests, and establishing new settlements.44 Afterwards, in around 1025, the Cholas ravaged its main commercial rival in the Indian Ocean, the Southeast Asian kingdom of Srivijaya. One of their goals was to take over the trade across the Kra Isthmus – the narrowest point of the Malayan Peninsula – which formed ‘the general rendezvous of the ships of Siraf and Oman, where they meet the ships of China’.⁴⁵

In India itself, the Cholas were at loggerheads with an alliance of Pandyan princes, who wanted to rid themselves of the Chola yoke. When they refused to pay their tribute, the Cholas razed the ancient Pandyan coronation hall, which merely intensified resistance. The Pandyans turned for support to rebellious princes in Sri Lanka and to the Chalukya kingdom – ‘the terror of the Cholas’.⁴⁶ For decades, the Chalukyas and the Cholas, both Hindu kingdoms, had been locked in conflict over the fertile valleys and trade routes of the Deccan Plateau. The Vikramankadevacarita – a famous hagiography of the Chalukya king Vikramaditya VI (1076–1126) – described how ‘The Chola again became proud and insolent’, eliciting fear in their neighbours.⁴⁷ When attempts to conciliate them failed, war followed. But it was the Cholas who were defeated and forced to sue for peace by sending an ambassador to offer a princess in marriage to the triumphant Chalukya king.

It was divisions like these that encouraged foreign invaders from the north and benefited them when they attacked. Chinese and Muslim visitors were impressed by the size of Indian armies and by the ‘necklace’ of fortresses built by the northern kingdoms to defend the main routes from Central Asia, the so-called ‘Gates of Hind’.⁴⁸ But, in the late eleventh century, neither succeeded in stemming a new wave of assaults. These were mounted by warlords originating from Khorasan, known as the Ghurids. ‘The lords of the horse’, the terrified Indians called them – as well as ‘beef-eating barbarians’, in recognition of their Islamic faith.49 The kingdoms and tribes in the north offered fierce resistance, and depicted the Ghurids as the common enemy of all Hindus. But the main Hindu powers, such as the Chalukyas, were located far away from the fighting and initially showed little solidarity. This left the smaller realms exposed to relentless attacks from the Ghurids’ mobile squadrons of horse archers, against which their infantry struggled to cope. After the Ghurid cavalry had inflicted serious losses on the northern Indian states between 1175 and 1186, resistance weakened. The Gates of Hind were now wide open; and yet more Ghurids poured in. In 1198, a great mosque was opened in Delhi to mark the establishment of Muslim rule in India.

Alliances Conducted at Sea

Despite the ways that the nomadic and tribal cultures of Eurasia had grown in strength and sophistication over the centuries, both the Byzantine and Song Empires still held to many of their ancient imperial traditions when it came to diplomatic dealings with them. Both still maintained dedicated offices to handle ‘barbarian’ affairs, although their main purpose was really no more than to manage protocol when envoys appeared at court. Those envoys’ primary task continued to be to convey written or oral messages between monarchs. At the same time, diplomacy became to some degree global, or at least transcontinental, particularly along the Silk Road. Perhaps most remarkably, the Byzantine emperor Michael VII dispatched an envoy to the Song court in 1078 to negotiate a coalition against the Seljuks. The Song, however, considered the Byzantines’ representative as an ordinary tribute payer. ‘They have during former dynasties not sent tribute to our court. During the tenth month of the 4th year of the period Yüan-feng, their king, Mieh-li-i-ling-kai-sa, first sent the ta-shouling [high official] Ni-ssu-tu-ling-ssu-meng-p’an to offer as tribute saddled horses, sword-blades, and real pearls.’50 This did not prevent the dispatch of another Byzantine mission, which was received in 1091.

In medieval Europe, churchmen and scholars – the two were indistinguishable – remained the main actors of diplomacy between states. They were also prominent in the pursuit of reconciling differences peacefully. St Francis of Assisi, for example, was one of the main advocates of tolerance and peace within the Christian community of the early thirteenth century; he even journeyed to Cairo in 1219 to try to end the Crusades by converting the Ayyubid sultan.

Increasingly, however, the period saw the papacy attempt to advance its spiritual and political authority through diplomatic endeavours. As well as sponsoring peace conferences, one of the chief papal strategies involved identifying common adversaries and seeking to build coalitions against them. Two of the chief targets were the Normans, whose ventures in Italy from the mid-eleventh century onwards were regarded by the popes as posing a threat to their security, and the Holy Roman Emperor. Pope Leo IX (1049–54), for example, referred to ‘the most evil nation of the Normans’ and called for the liberation of Christianity from the clutches of the Holy Roman Empire.51 Gregory VII (1073–85), meanwhile, spoke of the Church as ‘the legion of Christ’ and promoted the idea of a ‘militia of St Peter’ recruited from knights across Europe to defend papal interests. In 1177, Venice hosted a large peace conference to try and resolve the long-standing differences between the Holy Roman Emperor, the papacy and its allies among the city states of Northern Italy, and the Norman kingdom of Sicily. A follow-up conference, held in Constance in 1183, confirmed the autonomy of the northern city states from imperial control.

The greatest common enemy of the Middle Ages, however, was Islam. In 1095, Pope Urban II summoned a conference to Clermont to call for unity and what would be the start of a holy war against the Muslims in the Levant that lasted for almost 200 years. ‘You have seen for a long time the great disorder in the world,’ he lamented. ‘Although, O sons of God, you have promised more firmly than ever to keep the peace among yourselves and to preserve the rights of the church, there remains still an important work for you to do,’ the pope continued. ‘For your brethren who live in the east are in urgent need of your help … For, as the most of you have heard, the Turks and Arabs have attacked them.’⁵²

The Crusades, as a multinational endeavour, were responsible for stimulating much medieval diplomacy. The crusader Geoffrey of Villehardouin, for example, observed how the barons that led the Fourth Crusade (1202–4) first held a summit at Soissons, then appointed envoys with full authority to negotiate, and subsequently sent them to Venice to ask for assistance. In Venice, the crusaders’ delegates first had to make their case to the doge, then to the Great Council, and finally to a plenary session of the popular assembly in St Mark’s Square – in a manner that recalls Thucydides’ account of the Corcyran envoys addressing the Spartans and the Athenians. According to Geoffrey of Villehardouin, who acted as the crusaders’ spokesman, they had been told ‘to prostrate ourselves at your feet and not to get up until you have agreed to take pity on the Holy Land overseas’.53 Venice consented to help, but continued to trade with the crusaders’ enemies at the same time.

As this episode reveals, expediency was just as important as principles in determining medieval diplomatic strategy. Political alliances and trade agreements were forged and broken with equal impunity, while the force of circumstance overrode all. In 1096, for example, Urban II was prepared to help negotiate a peace on behalf of the duke of Normandy so that the latter could lead his army on the First Crusade. Around 1150, the abbot of the influential monastery of Cluny encouraged the Holy Roman Emperor and the Normans to make peace so that they could join in taking revenge on ‘the worthless ruler’ of the Byzantines for his role in the failure of the Second Crusade (1147–9). The Italians may generally have despised the Byzantines, too, but when Frederick Barbarossa descended on the northern cities in the 1170s, they scurried to secure Byzantine aid. After the sack of Constantinople in 1204, the Byzantines themselves were prepared to seek an alliance with their arch-enemies, the Seljuks, in their desperation to eject the crusaders from their capital. In 1220, Venice also signed trade agreements with the Seljuk sultans which provided for the mutual protection of ships and traders as well as the recognition of property rights.54

The Mongols, the other great common enemy of Christianity, did not elicit a united stance either. Some crusaders saw the Mongols as allies against the Muslims. Despite the stories of horrific Mongol atrocities emanating from the East, Pope Honorius III (1218–27) regarded the Mongols as potential associates in the fight against Islam, while Venice signed a trade treaty with the Mongols and rumours circulated that the French had tried to goad the Mongols into attacking the Holy Roman Empire.⁵⁵ But after the Mongols devastated Hungary in 1241, Pope Innocent IV called for a common front, a ‘remedy against the Mongols’. In preparation for a council of European leaders in 1245, Innocent sent the Franciscan monk John of Plano Carpini, laden with gifts, to the court of the Mongol khan. His main task was to gain information about the plans of the Mongols concerning Europe and to deliver two letters from the pope explaining the Christian faith and calling for peace. Was not the whole world united by bonds of natural affinity, suggested the pope, and should not all men follow the teachings of Christ and ‘live united in concord in the fear of God’?⁵⁶ Güyük Khan countered by proposing that if the pope and his fellow European rulers really wanted peace they should offer him fealty. In 1248, the first two Mongol envoys to Western Europe arrived in Rome where they delivered a blunt message: their khan was ordained by the gods to rule the whole world. Nevertheless, diplomatic endeavours continued. Over the next few years, Louis IX of France dispatched further envoys to the Mongols to try to convince them to aid a crusade to the Holy Land, while the Genoese hoped to be granted access to trade in the Black Sea region, which the Mongols controlled.

At the opposite end of Eurasia, in China, diplomatic practice was also characterized by opportunism. The Song brokered temporary alliances with the Tibetans, the Xia, the Jin, and many others – including even the Mongols. Sometimes these treaties were meant to sow discord so that other powers did not unite against them; at others their purpose was to obtain a truce that would allow the overstretched imperial troops time to regroup. The eminent Song official Tong Guan was a particular advocate of secretly negotiated deals, which came to be known as ‘alliances conducted at sea’.

Like their European counterparts, the Song court recruited many of their envoys from the ranks of the intelligentsia, although the strategy did not always pay dividends. On one occasion, in 1075, the great polymath Shen Kuo was called in to try and break an impasse in long-running discussions with the Liao. For years, the Song and the Liao had been trying to fix their common border: cartographers had surveyed the region to create meticulous new maps, while other experts had researched historical precedents and legal arguments – but to no avail.57 Shen Kuo and his staff spent further months trawling the imperial archives in search of fresh evidence to back the Song claim and learning their case by heart. But when they were finally admitted to the presence of the Liao king, all their assiduous efforts were angrily dismissed out of hand.⁵⁸

The fiasco surrounding the negotiations between the Southern Song and the Jin in the early 1140s was arguably even worse. Although both states agreed on the Yellow River as their border, the treaty lasted barely a year before hardliners on both sides, who considered its terms humiliating, sparked a new war. Concerned that the conflict was making his generals too powerful, the Song emperor appointed the senior official Qin Hui to negotiate peace. Qin was a prominent member of the peace party at court; he had also been a hostage of the Jin, developing close relations with them. Qin began by having the Song generals responsible for the war arrested and executed – a misstep that left the army leaderless and gave the Jin the upper hand in the rest of the negotiations. When the Treaty of Shaoxing was signed in 1141, the border had been shifted south almost to the River Yangtze – many miles in the Jin’s favour – an immense indemnity had been forced on the Song, and their state was referred to as ‘insignificant’.59 The public outcry at what was widely perceived to be Qin Hui’s treachery was immense, and has been used to fuel Chinese patriotism ever since.⁶⁰ Even today, in the former Song capital of Hangzhou, citizens passing by the tomb of Qin’s victims still spit on his kneeling statue.

Why Europe?

The Mongol expansion was the most important political event between 1000 and 1250. Like the Scythians and the Huns before them, the Mongols enjoyed unequalled mobility across the Eurasian landmass via the long grass highway of the steppes that extend from Mongolia to Eastern Europe. In common with previous nomadic invasions, climate change also formed an important destabilizing factor: it was a period of exceptionally cold summers that forced the Mongols from their homeland. Their invasions were decisive in determining the distribution of power: they caused long-term instability and economic decline in Asia, but they left Western Europe unscathed to continue its heretofore unremarkable development.

This outcome was largely the consequence of geography. Both Western Europe and China were politically fractured: China between the Southern Song, the Jin, and the Xia; Western Europe between France, the Holy Roman Empire, and several other smaller powers. In both regions, the failure of polities to unite against the common Mongol threat produced a domino effect as the Mongols were able to deploy the resources of states they had conquered in the periphery against the centres of power. The only significant difference between the two scenarios is one of distance. The Mongol heartland of the Orkhon Valley is about 1,500 kilometres from the North China Plain and 6,500 kilometres from the nearest fringes of Western Europe. As a result, the Mongols could never muster the same forces in the west as in the east; and it was quite understandable that the Mongol troops did not attempt to return to Western Europe after they had trekked back east to bury their khan. At the same time, the ongoing fragmentation of the Muslim world meant that Western Europe had far less to fear from its southern borders than in previous centuries and could devote itself to propagating the seeds of development that had started to sprout since the year 1000. This ‘lucky break’ would prove crucial in Europe’s history.