Jalal ad-Din Mengübirti had come to power…
February 1221 CE
Jalal ad-Din Mengübirti had come to power in 1220 following the defeat of his father, the Khwarezm Shah Ala ad-Din Muhammad II, by Genghis Khan, but rejects the title shah that his father had assumed, calling himself simply sultan.
Jalal ad-Din has retreated with the remaining Khwarazmian forces, while pursued by a Mongol army, and at the battle of Parwan, near Ghazni, he defeats the Mongols.
The minor rout at Parwan inspires the cities of Herat and Merv to rebel, resulting in their destruction on the orders of Genghis Khan.
Due to the Mongol invasion, the sacking of the capital city of Samarkand, and the desertion of his Afghan allies, Jalal ad-Din is forced to flee to India.