The French crusader Godfrey of Bouillon (ca. 1060-1100) was one of the chief lay leaders of the First Crusade and the first ruler of the newly formed state of Jerusalem.

Godfrey was the second son of Eustace II, Count of Boulogne, and Ida, daughter of Godfrey II, Duke of Lower Lorraine. After years of delay Emperor Henry IV finally confirmed him in the duchy of Lower Lorraine. When he and his brothers, Eustace and Baldwin, joined the First Crusade, Godfrey was nevertheless obliged to pledge his castle in Bouillon, as well as the lordship of Verdun, to the bishop of Liège, presumably to help finance the expedition.

The crusaders reached Constantinople shortly before Christmas, 1096. For several months there were promises and betrayals and armed skirmishes with the Byzantine troops. Finally the whole force of crusaders, now swelled by the Norman contingent and Bohemund's army, crossed the Bosporus and set out for Nicaea. When Jerusalem was captured in July 1099, the higher clergy and the greater barons offered the crown to Godfrey, having failed to convince Count Raymond to take it. Godfrey accepted the leadership but claimed instead the title of Advocatus Sancti Sepulchri (Defender of the Holy Sepulcher). This made him lay warrantor of the newly won lands, allowing the Church to preserve, initially, its own interests. The ecclesiastical claims to Jerusalem and its dependent towns were advanced by the forceful Daimbert, Archbishop of Pisa, who, backed by Bohemund, became patriarch a short time later. Godfrey, who in reality had little effective power, took an oath of homage to Daimbert and managed to retain control of his small state until his death on July 18, 1100, near Tiberias. According to Moslem sources, he was killed in battle.

Godfrey was the first Western ruler in Jerusalem, and this undoubtedly helped form the legend in later literature in which he was transformed into the model for the valorous Christian knight, the Chevalier au Cygne (Swan Knight). Dante, in the Divine Comedy, places him with the warrior-saints in Paradise. There is, however, no reliable evidence for his unusual piety or for his extraordinary chivalric qualities. His chief accomplishment remains the establishment of a workable feudal administration in Jerusalem based on customary fief holding and oaths of loyalty. That he was able to do this in the face of overt and continual hostility from friends and enemies says much about the character of the man.