 As early as 1464, Uzun Hasan had requested military aid from one of the Ottoman Empire's strongest enemies, Venice.Despite Venetian promises, this aid never arrived and, as a result, Uzun Hassan was defeated by the Ottomans at the Battle of Otlukbeli in 1473, though this did not destroy the Aq Qoyunlu.When Uzun Hasan died early in 1478, he was succeeded by his son Khalil Mirza, but the latter was defeated by a confederation under his younger brother Ya'qub at the Battle of Khoy in July.