Kara Yuluk Osman

Qara Osman (Azerbaijani: Qara Yuluq Osman Bəy, Turkish: Kara Yülük Osman Bey) (reigned 1378–1435) was a late 14th and early 15th-century leader of the Turkmen tribal federation of Aq Qoyunlu in what is now eastern Turkey, Iran, Azerbaijan and Iraq.

He was born Baha-ud-Din Osman and later given the nickname Qara Iluk or Qara Yuluk meaning The Black Leech. According to Byzantine and Aq Qoyunlu sources, he was married to a princess, a daughter of Alexios III of Trebizond and his consort Theodora Kantakouzene.

He was afraid of the intentions of his brothers, Ahmed and Pir Ali, when they joined Kadi Burhan al-Din of Sivas. He eventually killed his opponents and took over their territories in 1398 but retreated from Erzinjan on arrival of the Ottomans under Süleyman Çelebi.

When Timur invaded the Caucasus and eastern Anatolia, the Aq Qoyunlu sided with him in support and fought alongside the Timurids against the Ottomans. For his services Qara Osman was given Diyarbakır in 1402.

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