Battle of Köse Dağ

Anatolian history

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June 30, 2026

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The Battle of Köse Dağ, fought in 1243, was a pivotal event in Anatolian history. The Seljuq sultan Ghiyās al-Dīn Kay-Khusraw II was decisively defeated by the Mongol commander Bayju near Sivas and Erzincan. This loss rendered the Anatolian Seljuqs vassals to the Mongols.1

Following this battle, Mongol power in Anatolia led to a period of fragmentation. Although Mongol power collapsed in 1335, it paved the way for the rise of various principalities, known as beyliks, and ultimately the Ottoman Empire. The Seljuq realm experienced further division and decline, with Mongol troops stationed throughout Anatolia, diminishing the authority of the Seljuq sultans.12

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Seljuq
At the Battle of Köse Dagh in 1243, Seljuq autonomy was lost forever. For a time the Seljuq sultanate continued as a Mongol province, although some Turkmen emirs maintained small principalities of their own in distant mountainous districts. The Seljuq dynasty died out at last early in…
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At the Battle of Köse Dagh in 1243, Seljuq autonomy was lost forever. For a time the Seljuq sultanate continued as a Mongol province, although some Turkmen emirs maintained small principalities of their own in distant mountainous districts. The Seljuq dynasty died out at last early in…
Read More

Anatolia
Seljuq expansion
…the Mongol commander Bayjū at Köse Dağ between Sivas and Erzincan, and the Anatolian Seljuqs passed under Mongol suzerainty as vassals. Kay-Khusraw II fled to Antalya, leaving his minister to come to terms with the Mongols. Cilician Armenia transferred its loyalty to the Mongols, and Turkmen revolts broke out along…
Read More
…the Mongol commander Bayjū at Köse Dağ between Sivas and Erzincan, and the Anatolian Seljuqs passed under Mongol suzerainty as vassals. Kay-Khusraw II fled to Antalya, leaving his minister to come to terms with the Mongols. Cilician Armenia transferred its loyalty to the Mongols, and Turkmen revolts broke out along…
Read More