Emperor Taizong of Tang (r. 626-649), the second emperor of Chinese dynasty Tang Dynasty, throughout most of his reign, faced challenges from Tang's western neighbor, the state of Tuyuhun, whose Busabuo Khan Murong Fuyun constantly challenged Chinese authority in the border regions. In 634, Emperor Taizong launched a major attack, commanded by the major general Li Jing, against Tuyuhun, dealing Tuyuhun forces heavy defeats and causing Murong Fuyun's subordinates to assassinate him in 635. Tuyuhun, thus weakened, no longer remained a major power in the region, and while Tang, ironically, played the role of protector for Murong Fuyun's son, the Gandou Khan Murong Shun, and grandson, the Ledou Khan Murong Nuohebo, Tuyuhun was never able to recover, particularly with its southwestern neighbor