Kaidu ( "Qaidu", Cyrillic: Хайду; ) (c. 1230 – 1301) was a grandson of the Mongol khagan Ögedei (1185–1241) and thus leader of the House of Ögedei and the "de facto" khan of the Chagatai Khanate, a division of the Mongol Empire. He ruled part of modern-day Xinjiang and Central Asia during the 13th century, and actively opposed his cousin, Kublai Khan, who established the Yuan dynasty in China, until Kaidu's death in 1301. Medieval chroniclers often mistranslated Kadan as Kaidu, mistakenly placing Kaidu at the Battle of Legnica. Kadan was the brother of Güyük, and Kaidu's uncle.