| c.400 | Augustine of Hippo outlines a Christian theory of just war |
| 638 | Jerusalem is captured by the Arabs under Caliph Umar |
| 800 | Charlemagne the Frank is crowned Roman Emperor of the West |
| 9th century | Holy wars proclaimed against Muslim invaders of Italy |
| 11th century | Church approval for wars against Muslim rulers in the western Mediterranean |
| 1053 | Pope Leo IX offers remission of sins to his troops fighting the Normans of southern Italy |
| 1050s-70s | Seljuk Turks invade the Near East |
| 1061–91 | Norman conquest of Muslim Sicily with papal support and spiritual privileges |
| 1071 | Seljuk Turks defeat Byzantines at Manzikert; they overrun Asia Minor and establish a capital at Nicaea |
| 1074 | Pope Gregory VII proposes a campaign from the west to help Byzantium against the Turks and to liberate the Holy Sepulchre |
| 1095 | Byzantine appeal to Pope Urban II for military aid against the Turks; Urban II’s preaching tour of France (ends 1096); Council of Clermont proclaims Crusade |
| 1096–99 | First Crusade; Jerusalem captured (15 July 1099) |
| 1101 onwards | Smaller crusades to the Holy Land |
| 1104 | Acre captured |
| 1107–8 | Crusade of the First Crusade hero Bohemund of Taranto against Byzantium |
| c.1113 | Order of the Hospital of St John in Jerusalem recognized |
| 1114 onwards | Crusades in Spain |
| 1120 | Order of the Temple founded in Jerusalem to protect pilgrims |
| 1120s | Order of St John, the Hospitallers, beginning to become militarized |
| 1123 | First Lateran Council extends Jerusalem privileges to Spanish crusades and defines Church protection for crusaders |
| 1144 | Edessa captured by Zengi of Aleppo, leading to Eugenius III’s bull Quantum praedecessores in 1145/6, which also outlines a range of crusader privileges |
| 1145–9 | Second Crusade of Louis VII of France and Conrad III of Germany; Dartmouth Commune and siege of Lisbon 1147 |
| 1149 onwards | Further crusades in Spain and, from the 1190s, the Baltic; small expeditions to the Holy Land |
| 1163–9 | The Franks of Jerusalem contest control of Egypt |
| 1169 | Saladin succeeds as ruler of Egypt |
| 1174 | Saladin begins to unify Syria with Egypt |
| 1187 | Battle of Hattin; Jerusalem falls to Saladin; Gregory VIII’s bull Audita Tremendi |
| 1188–92 | Third Crusade of Frederick I Barbarossa of Germany, Philip II of France and Richard I of England; 1190 Philip II’s treaty with Genoa; siege of Acre 1189–91; Richard I conquers Cyprus 1191 |
| 1190–91 | Foundation of Teutonic Order |
| 1193–1230 | Crusades to Livonia in the Baltic |
| 1195–6 | Henry VI of Germany launches German crusade |
| 1198 | Pope Innocent III proclaims Fourth Crusade |
| 1199 | Church taxation instituted for the Crusade by Innocent III |
| 1201–4 | Fourth Crusade; Treaty of Venice 1201; fall and sack of Constantinople 1204 |
| 13th century | Crusades in the Baltic by Teutonic Knights (Prussia), Sword Brothers (Livonia); Danes (Prussia, Livonia, Estonia) and Swedes (Estonia and Finland) |
| 13th century | Crusades against German peasants, Bosnians, etc. |
| 1208–29 | Albigensian Crusade |
| 1212 | Children’s Crusade |
| 1213 | Innocent III proclaims Fifth Crusade in bull Quia Maior, which extends crusade privileges to those who contribute but do not go on crusade |
| 1217–21 | Fifth Crusade; siege of Damietta 1218–19 |
| 1228–9 | Crusade of Frederick II of Germany |
| 1231 onwards | Crusades against the Byzantines to defend western conquests in Greece |
| 1234 | Gregory IX’s crusade bull Rachel suum videns consolidates vow redemption system |
| 1239–68 | Crusades against Hohenstaufen rulers of Germany
and Sicily |
| 1239–41 | Crusades to the Holy Land of Theobald, count of Champagne and Richard, earl of Cornwall; Mongol attacks penetrate eastern Europe |
| 1244 | Jerusalem lost to Muslims; Louis IX of France takes the Cross |
| 1245 | First Council of Lyons held by Innocent IV grants crusade taxes |
| 1248–54 | First crusade of Louis IX of France; invasion of Egypt and defeat 1249–50 |
| 1251 | First Shepherds’ Crusade |
| 1260 | Mamluks repulse Mongols from Syria |
| 1261 | Greeks recover Constantinople |
| 1267 | Louis IX takes the Cross again |
| 1270 | Louis IX’s second crusade to Tunis, where he dies |
| 1271–2 | Crusade to the Holy Land of Lord Edward, later Edward I of England |
| 1274 | Second Council of Lyons held by Gregory X; advice sought; crusade taxes agreed; collection regions fixed; crusade bull Zelus fidei |
| 1291 | Fall of Acre to al-Ashraf Khalil of Egypt and evacuation of mainland Outremer; failure of Pope Nicholas IV to launch crusade despite crusade taxes authorized; flood of crusade advice until mid-14th century |
| 1330s | Aborted crusade of Philip VI of France |