Baldwin I (Dutch: Boudewijn; French: Baudouin; July 1172 – c. 1205) was the first emperor of the Latin Empire of Constantinople; Count of Flanders (as Baldwin IX) from 1194 to 1205 and Count of Hainaut (as Baldwin VI) from 1195-1205. Baldwin was one of the most prominent leaders of the Fourth Crusade, which resulted in the sack of Constantinople in 1204, the conquest of large parts of the Byzantine Empire, and the foundation of the Latin Empire. He lost his final battle to Kaloyan, the emperor of Bulgaria, and spent his last days as his prisoner.