Battle of the Kalka

On 23 May 1223, near the town of Kalka, the combined forces of the Rus' principalities and their Cuman allies clashed with the advancing Mongol army led by Subutai.

After conquering Khwarazm, Genghis Khan assembled his army in Persia and Armenia. At Subutai's suggestion, the Mongol army split into two parts. In 1223, Genghis Khan led the main army on a campaign in Afghanistan, northern India and Iran. He defeated every army that opposed him, thereby incorporating Transoxiana and Persia into the Mongol Empire.

Meanwhile, a corps of twenty thousand soldiers under Subutai and Jebe passed through Georgia and captured the Genoese colony of Caffa in Crimea. This was the Mongols' first incursion into Europe. During their return, Subutai's troops attacked the armies near the town of Kalka.

Although the battle ended in complete defeat for the Rus' principalities and their allies, the Mongol army was exhausted, and Subutai decided to withdraw temporarily.

During this withdrawal, the Mongols passed through the Volga region and the territory of Volga Bulgaria. After the Battle of the Kalka River and the allies' defeat, Chelbir recognised the danger and began preparing for war. Realising that Genghis Khan's army under Subutai was invincible, he ordered troops to assemble and began preparations for the approaching conflict. Several Cuman detachments and the Mordvin princes Puresh and Purgaz joined his army.