In 1122 the Doge of Venice, Domenico Michiel, launched the seaborne crusade.[6] The Venetian fleet of more than 120 ships carrying over 15,000 men left the Venetian Lagoon on 8 August 1122.[3] This seems to have been the first crusade in which the knights brought their horses with them.[7] They invested Corfu, then a possession of the Byzantine Empire, with which Venice had a dispute over privileges.[6] In 1123 Baldwin II was captured by Balak of Mardin, emir of Aleppo, and imprisoned in Kharput. Eustace Graverius became regent of Jerusalem.[1] The Venetians abandoned the siege of Corfu when they heard this news, and reached the Palestinian coast in May 1123.[6]