Origins

The Crusading movement began at the Council of Clermont in November 1095, where Pope Urban II preached a sermon calling on Western Christian knights to travel to the eastern Mediterranean to recover the holy places from Muslim control. The immediate trigger was a request for military aid from the Byzantine Emperor Alexios I Komnenos, whose territory had been substantially reduced by the Seljuk Turkish advance after the Battle of Manzikert in 1071.

Urban offered a plenary indulgence — full remission of sins — to those who took up the cross. Within a few months, tens of thousands of Western Europeans, from peasants to kings, had committed to the expedition.

The First Crusade

The First Crusade (1096–1099) was the most successful from the crusaders’ point of view. Four major armies marched east, captured Antioch (1098) after a long siege, and stormed Jerusalem on 15 July 1099. The capture of Jerusalem involved a substantial massacre of the city’s Muslim and Jewish populations. Four Crusader states were established along the eastern Mediterranean coast: the County of Edessa, the Principality of Antioch, the County of Tripoli, and the Kingdom of Jerusalem.

The First Crusade also produced the Rhineland pogroms of 1096, in which the Jewish communities of Speyer, Worms, Mainz, and Cologne were attacked by crusading mobs en route to the east. Approximately 5,000 Jews were killed in the spring and summer of 1096. The pattern would be repeated, with different perpetrators, during the Black Death pogroms of 1349.

The subsequent crusades

The historiographic convention numbers nine major crusades. The most consequential were:

Second Crusade (1147–1149). Triggered by the loss of Edessa to Muslim forces. Largely unsuccessful.

Third Crusade (1189–1192). Triggered by Saladin’s recapture of Jerusalem in 1187. Led by the English king Richard I (the Lionheart), the French king Philip II, and the German emperor Frederick Barbarossa (who drowned en route). Recaptured the coastal city of Acre but failed to retake Jerusalem.

Fourth Crusade (1202–1204). Originally aimed at Egypt; diverted by Venetian financial pressure to attack and sack Constantinople in April 1204, splintering the Byzantine Empire and severely damaging relations between the Catholic and Orthodox Christian churches.

Children’s Crusade (1212). Now generally believed by historians to have been a youth movement of unemployed adult laborers (the Latin pueri could mean “boys” or “lads”) rather than literal children.

Fifth through Ninth Crusades (1217–1272). A series of largely unsuccessful campaigns against Egypt and the Holy Land. King Louis IX of France led two of them (1248–1254 and 1270) and died in Tunis on the second.

The last Crusader stronghold, Acre, fell to the Mamluk Sultanate on 18 May 1291.

Other crusades

The Crusading idea was extended to other targets:

  • The Reconquista (Spain, 711–1492) was treated as a crusade after 1212.
  • The Northern Crusades (Baltic, 1147–1290) targeted pagan Lithuanians, Estonians, Finns, and Slavs and produced the territories that would become the Baltic states.
  • The Albigensian Crusade (southern France, 1209–1229) was directed against the Cathar Christian movement and effectively destroyed it.
  • Anti-Hussite crusades (Bohemia, 1420–1431) failed.

Legacy

The Crusades shaped the medieval and early modern Mediterranean. They transferred substantial scholarly and material goods from the Islamic world to Christian Europe. They established the military religious orders — the Templars, the Hospitallers, the Teutonic Knights — that would influence European military and political life for centuries. The Hospitallers in particular continued as a political-military force, controlling Rhodes (1310–1522) and Malta (1530–1798) and surviving as a sovereign Catholic chivalric order to the present day.

The Crusades also produced a long legacy of Christian-Muslim mutual suspicion that has been invoked in subsequent conflicts up to the present.