Hi Mirmillo,
Mongol Empire:
Mongol Invasion of Central Asia:(
link )
It would be the invasion and utter destruction and complete devastation of the Khwarezmid Empire which would earn the Mongols the name for bloodthirsty ferocity that would mark the remainder of their campaigns. In this brief war, lasting less than two years, not only was a huge empire destroyed utterly, but Genghis Khan introduced the world to tactics that would not be seen again until the Germans used them so well in World War II - indirect attack, and complete and utter terror and slaughter of populations wholesale as weapons of war.(quoted from above link.-added reference there-Nicolle, David. The Mongol Warlords.)
When the city of Urgench was assaulted and finally brought to its heels:As usual, the artisans were sent back to Mongolia, the young women and children were given to the Mongol soldiers as slaves, and the rest of the population was massacred. The Persian scholar Juvayni states that 50,000 Mongol soldiers were given the task of executing twenty-four Urgench citizens each, which would mean that 1.2 million people were killed. While this is almost certainly exaggeration, the sacking of Urgench is considered one of the bloodiest massacres in human history. reference in the above link: Saunders, J.J. The History of the Mongol Conquests
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