25 August 1227
Genghis Khan (pronounced /ˈdʒɛŋɡɪs ˈkɑːn/ or /ˈɡɛŋɡɪs ˈkɑːn/; Mongolian: Чингис Хаан, Čingis Xaan, or ᠴᠢᠩᠭᠢᠰ ᠬᠠᠭᠠᠨ, Činggis Qaγan), IPA: ( listen); (probably May 31, 1162 or 1159 – August 25, 1227), born Borjigin Temüjin pronunciation (help·info), was the founder, Khan (ruler) and Khagan (emperor) of the Mongol Empire, which became the largest contiguous empire in history after his death.
He came to power by uniting many of the nomadic tribes of northeast Asia. After founding the Mongol Empire and being proclaimed "Genghis Khan", he started the Mongol invasions that would result in the conquest of most of Eurasia. These included raids or invasions of the Kara-Khitan Khanate, Caucasus, Khwarezmid Empire, Western Xia and Jin dynasties. These campaigns were often accompanied by wholesale massacres of the civilian populations – especially in Khwarezmia. By the end of his life, the Mongol Empire occupied a substantial portion of Central Asia and China.