Gao Xianzhi
In 751, after Emperor Xuanzong met with and was impressed by the ethnically Goguryeo general Gao Xianzhi, who was then military governor of Anxi Circuit (安西, headquartered in modern Aksu Prefecture, Xinjiang), he issued an order making Gao the military governor at Hexi. However, An encouraged the non-Han chieftains under his command to cut off their ears and lacerate their faces and request that Emperor Xuanzong allow An to remain at Hexi, and Emperor Xuanzong did so.