Jalal ad-Din Mingburnu was fleeing to India with his men together with thousands of refugees from Persia, following the Mongol sacking of several cities, including Bukhara and Samarkand, the latter being the Khwarezmian capital. After having won the Battle of Parwan, near the city of Ghazni, Jalal ad-Din Mingburnu headed for India to seek refuge together with his army of some fifty thousand men and several thousand refugees. However, the army of Genghis Khan caught up with him when he was about to cross the river Indus.
Jalal al-Din Khwarazm-Shah crossing the rapid Indus river, escaping Genghis Khan and his army
Jalal al-Din positioned his army of fifty thousand men in a defensive stance against the Mongols, placing one flank against the mountains while his other flank was covered by a river bend. The initial Mongol charge, opening the battle, is beaten back. Jalal al-Din counterattacks, nearly breaching the center of the Mongol army, while Genghis sends a contingent of ten thousand men around the mountain and flanks Jalal al-Din's army. With his army attacked from two directions and collapsing into chaos, Jalal al-Din flees across the Indus river.