AHistoryIndependent states
The Battle of Yassıçemen (1230)
The battle near Erzincan between the Khwarazmshah Jalal al-Din and the Seljuk sultan Kayqubad I; this clash of two Turkic states opened the way for the Mongols.
Jalal al-Din Khwarazmshah, who had fought the Mongols for ten years, came to Azerbaijan in 1225 and founded a new state there. At first he negotiated an alliance with the Seljuks of Rum against the Mongols, but relations broke down. In 1230 he took Akhlat from the Ayyubids and joined Jahanshah, the Seljuk governor of Erzurum, against the sultan. In response Sultan Kayqubad I allied with the Ayyubids.
In August 1230 the armies met on the plain of Yassıçemen west of Erzincan. The Khwarazmian vanguard won the first clash, but allied reinforcements arrived. After three days of fighting the Seljuk-Ayyubid army prevailed and Jalal al-Din withdrew.
The victory gave the Seljuks a brief respite, but historians count it a bitter mistake by two Turkic states. The last force standing between the Mongols and Anatolia, Jalal al-Din's realm, fell apart. Jalal al-Din was killed in 1231, and twelve years later the Mongols defeated the Seljuks themselves at Köse Dağ.
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Updated: November 11, 2026