May 1, 1221
1221 battles involving the Mongol Empire
1221 failed Estonian siege of the Danish stronghold in the Livonian Crusade
Khwarezmian Empire vs Mongol Empire, 1221
1221 Mongol invasion of Khwarezmia and Eastern Iran
Mongol campaign in 1220–1221
Battle fought at the Indust river between Khwarazm and the Mongols (1221 AD)