The siege of Bukhara took place in February 1220, during the Mongol conquest of the Khwarazmian Empire. Genghis Khan, ruler of the Mongol Empire, had launched an assault on the Khwarazmian Empire after being provoked by Shah Muhammad II. Genghis personally led a force of between 30,000 and 50,000 warriors across the Kyzylkum Desert to surprise the defenders of Bukhara. This city had been thought to be far from danger, and so was garrisoned by fewer than 20,000 men. After a failed sortie, the outer city surrendered on 10 February. Khwarazmian loyalists continued to defend the citadel for a further ten days, before it was breached and taken. Most of the city's population was enslaved or conscripted. Although Bukhara was then destroyed by fire, the destruction was relatively mild compared to that suffered by other cities conquered by the Mongols; within a short space of time the city was once again a centre of trade and learning, and it profited greatly from the Pax Mongolica. (Full article...)