Baldwin I (Dutch: Boudewijn; French: Baudouin; July 1172 – c.?1205) was the first emperor of the Latin Empire of Constantinople.
As Count of Flanders and Hainaut, he was one of the most prominent leaders of the Fourth Crusade, which resulted in the sack of Constantinople and 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.