Mongols and Il-Khans (1256-1353) in Iran. Mongolian tribes under Chingiz Khan first devastated Central Asia, Afghanistan and northern Iran in 1218-1223. They finally conquered the Islamic world under the leadership of Hulagu (a grandson of Chingiz Khan).The arts and sciences underwent a renaissance under the I. Khans, who especially fostered Persian historiography, mathematics, astronomy and medicine. Photo via Newscom