The Ottoman Empire was a Turkish state founded in the thirteenth century by Osman I, who then expanded his territories, eventually dislodging Byzantine rulers and taking over Constantinople in 1453. Constantinople, now called Istanbul, became the capital of the Ottoman Empire, which by the fifteenth century controlled large portions of North Africa, the Middle East, and the Mediterranean. The Ottoman Empire was one of the longest lasting powers in history, only falling in 1922 when Turkey became a republic.