* Meyer swore that the documents detailing French military secrets could not have been written by the accused, Alfred Dreyfus.

* At least four other copies of the History of William Marshal appear to have been made, but these, along with the original, were lost over the centuries.

* Henry’s father Geoffrey bore the nickname ‘Plantagenet’, probably because he habitually kept a sprig of broom (planta genista) in his helmet. However, the dynasty that followed him did not think of themselves as ‘Plantagenets’, and this term for the family line was not widely used until the seventeenth century.

* Some Anglo–Norman and Angevin nobles brought up in the west of England seem to have developed a noticeable accent, and were mocked as a result at the elitist Angevin court. By the later twelfth century a derisive story was circulating, suggesting that there was a cursed water spring in Marlborough and ‘whoever tastes it speaks bad French’, otherwise known as ‘Marlborough French’.

* A remarkable level of credence was also given to Merlin’s prophecies and it became fashionable to foretell future events on the basis of these arcane pronouncements, with some treating them as almost akin to Scripture. According to Ralph of Diss, William Marshal’s father, John, fell foul of this trend. John apparently made a public prediction, on the basis of ‘pseudo-prophets’, that Henry II would never return after his departure for the Continent in 1158. When the king duly landed back in England in January 1163, John lost royal favour.

* The notion that a trainee knight might be regarded as a ‘squire’ had yet to be formalised, so although the term ‘squire’ was sometimes used in this period, squires were often indistinguishable from servants, and not all such men went on to become fully fledged knights.

* The modern term ‘freelance’ actually derives from the famous fiction author Walter Scott’s use of the phrase ‘Free Lances’ in 1820 to describe unattached medieval warriors or mercenaries – men whose lances were literally for hire – in his novel Ivanhoe.

* It would appear that William Marshal’s mother, Sybil of Salisbury, had also died by this point, though her death was not recorded in the History.

* According to the courtier Walter Map, Marshal’s old patron, William, lord of Tancarville, was appointed as Eleanor’s military commander in Aquitaine after Patrick of Salisbury’s death, but if true, it is strange that this detail was not recorded in the History of William Marshal.

* While the History seems to have been mildly troubled by this profiteering, outside the immediate context of tournaments, Marshal’s biographer often took a more positive attitude to material gain. Perhaps the most striking example of this came in an incident drawn from the early 1180s, when William was journeying through northern France. He encountered a furtive couple on the road and intervened to ensure that the young woman was not being forced to travel under duress. It transpired that the pair were eloping lovers – a noble-born maiden and a runaway monk – hoping to start a new life together far from home. When the monk made the mistake of revealing a moneybag packed with £48 (funds with which the couple were hoping to finance their future), Marshal promptly confiscated the cash and sent them packing to a life of penury. The biographer clearly expected his medieval audience to applaud this behaviour – to view the lovers as transgressive social outcasts, subject to summary justice. Indeed, he even commended William’s unusual generosity in not stripping the pair of their clothes and horses.

* An English knight named ‘Ansel the Marshal’ also appeared in this long list. This may have been William Marshal’s younger brother. The History described him as ‘a noble, amiable man, brave and loyal’, but made no mention of his lineage.

* Walter’s summary execution caused local outrage, and the scandal may have had some connection with Philip’s decision to take the cross for a crusade in 1175. However, the accusation of adultery also enabled Philip to seize control of Isabel’s family lands in Vermandois, so it may be that the whole story of the affair was manufactured.

* The deathbed charge laid upon William Marshal was confirmed by Roger of Howden and the local contemporary chronicler Geoffrey of Vigeois, who described William as the Young King’s ‘carissimus’ – his most intimate or treasured associate.

* One of William Marshal’s other sisters, Margaret, married first Ralph of Somery, and later Maurice of Gant.

* According to Gerald of Wales, Richard the Lionheart later recounted Henry II’s spiteful comment to Philip Augustus and the Capetian court.

* Richard Strongbow of Clare, earl of Striguil had died in 1176. His son and heir Gilbert (Isabel’s brother) then died at the age of twelve in 1185, leaving Isabel as heir.

* William Marshal’s younger brother, Henry Marshal – who had entered the Church – also enjoyed rewards in this period, being appointed as bishop of Exeter.

* The festivities were marred by the outbreak of anti-Jewish rioting in London and Westminster, inspired in part, it would seem, by misdirected crusading fervour.

* William Marshal was also able to use Striguil as a minor port because of its position on the banks of the Wye and its close proximity to the River Severn.

* Other sources suggested that Queen Eleanor played a role in orchestrating a reconciliation, but the biographer seems to have been well informed on this episode because of William Marshal’s presence in Richard’s retinue.

* The History of William Marshal suggests that King John demanded another hostage from William Marshal at this point – his second son Richard Marshal, who was then around twelve years old. However, royal records indicate that Richard was not placed into the custody of the crown for more than a year (4 June 1208), so this appears to have been an error on the biographer’s part.

* A particularly ugly dispute broke out with the native Irish prelate, Albinus, bishop of Ferns, over lands that Marshal claimed as his own, and this caused the earl to be condemned by the Irish Church.

* Marshal’s well-established ally, Geoffrey FitzPeter, earl of Essex, offered a pledge in support of Earl William’s loyalty around this time (and stood as surety for Marshal’s willingness to surrender his castles to the crown, if called upon to do so). This pledge may have been connected to the release of John of Earley and Jordan of Sauqueville from custody.

* Peter des Roches hailed from the same dynasty as the knight William des Roches, though their precise familial relationship is unclear.

* This step was not unprecedented elsewhere in Europe, as a number of other realms, including Sicily, Portugal and Denmark, had previously accepted papal overlordship.

* This Anglo-French army initially marched north to relieve Mountsorrel, which had been besieged by Ranulf of Chester, but when he retreated, they quickly moved on to Lincoln.