In 1206, Temujin accepted the title Genghis Khan, or “universal ruler” of the Mongol clans. Over the next 21 years, Genghis led the Mongols in conquering much of Asia. His first goal was China. After invading the northern Jin Empire in 1211, however, his attention turned to the Islamic region west of Mongolia. Angered by the murder of Mongol traders and an ambas- sador at the hands of the Muslims, Genghis launched a campaign of terror across Central Asia. The Mongols destroyed one city after another—Utrar, Samarkand, Bukhara—and slaughtered many inhabitants. By 1225, Central Asia was under Mongol control.