Godfrey and his brothers Eustace III and Baldwin of Boulogne joined the First Crusade in 1096. He saw minor action at Nicaea, Dorylaeum and Antioch, before playing a key role during the successful Siege of Jerusalem in 1099. Raymond IV of Toulouse declined the offer to become king of Jerusalem, and Godfrey accepted the rulership instead. He refused the title of king, however, as he believed that he ought not wear "a crown of gold" where Jesus Christ had worn "a crown of thorns". Godfrey secured his kingdom by defeating the Fatimids at Ascalon a month later, bringing the First Crusade to an end.