The Battle of Otlukbeli was fought between the eastbound-proceeding Ottoman forces commanded by Sultan Mehmed II and the defending forces of Aq Qoyunlu () Turcomans under Uzun Hasan near Otlukbeli on August 11, 1473. The cause of the conflict was that Uzun Hasan maintained ties with the Byzantines, who moved to the east after the conquest of their capital Constantinople by Sultan Mehmed II in 1453. The battle lasted eight hours causing deaths of hundreds of thousands, and ended with the decisive victory of the Ottoman army, which used firearms and cannons not available to their enemy.