Battle of the Kalka River in the context of "Mongol invasion of Central Asia"

The Mongol Empire invaded and conquered much of the Kievan Rus' in the mid-13th century, sacking numerous cities such as Ryazan, Yaroslavl, Pereyaslavl and Vladimir, including the largest: Kiev (50,000 inhabitants) and Chernigov (30,000 inhabitants). The siege of Kiev in 1240 by the Mongols is generally held to mark the end of the state of Kievan Rus', which had already been undergoing fragmentation. Many other principalities and urban centres in the northwest and southwest escaped complete destruction or suffered little to no damage from the Mongol invasion, including Galicia–Volhynia, Pskov, Smolensk, Polotsk, Vitebsk, and probably Rostov and Uglich.

The Mongol campaign was heralded by the Battle of the Kalka River on 31 May 1223, which resulted in a Mongol victory over the forces of several principalities as well as the remnants of the Cumans under Köten. The Mongols retreated, having gathered their intelligence, which was the purpose of the reconnaissance-in-force. A full-scale invasion by Batu Khan followed, with most of Kievan Rus' overrun in 1236–1238. The Mongols captured Kiev in 1240 and moved west into Hungary and Poland. The heavy losses suffered by the Mongols during the invasion period significantly weakened subsequent campaigns, preventing the ruin of the Holy Roman Empire and more western countries.

Köten (Russian: Котян, romanized: Kotyan; Hungarian: Kötöny; Arabic: Kutan; fl. 1205–1241) was a Cuman–Kipchak chieftain (khan) and military commander active in the mid-13th century. He forged an important alliance with the Kievan Rus' against the Mongols but was ultimately defeated by them at the Kalka River in 1223. After the Mongol victory, Köten led 40,000 "huts" to Hungary, where he became an ally of the Hungarian king and accepted Catholicism, but was nonetheless assassinated by the Hungarian nobility.

The Kalchyk (Ukrainian: Кальчик) is a river in the Donetsk and Zaporizhzhia Oblasts of Ukraine. It is historically known as the Kalka. It flows into the Kalmius, which it enters near the city of Mariupol.

Supposedly, the river was the scene of the Battle of the Kalka River between the Mongol Empire and Kievan Rus' in 1223. It was also the scene of the decisive Battle of the Kalka River (1381) between Mamai and Tokhtamysh which ended the Great Troubles (1359–1381), a war of succession within the Golden Horde.