Jalal ad-Din Mingburnu (Persian: جلال ‌الدین خوارزمشاه; full name: Jalal ad-Dunya wa ad-Din Abul-Muzaffar Manguberdi ibn Muhammad) or Manguberdi (Turkic for "Godgiven"), also known as Jalâl ad-Dîn Khwârazmshâh, was the last ruler of the Khwarezmian Empire. Following the defeat of his father, Ala ad-Din Muhammad II by Genghis Khan in 1220, Jalal ad-Din Mengübirti came to power but he rejected the title shah that his father had assumed and called himself simply sultan. Jalal ad-Din retreated with the remaining Khwarazm forces, while pursued by a Mongol army and at the battle of Parwan, north of Kabul, defeated the Mongols.