房玄龄
Emperor Taizong also immediately faced a crisis, as the Eastern Turkish leader Jiali Khan Ashina Duobi, along with his nephew the subordinate Tuli Khan Ashina Shibobi (), launched a major incursion toward Chang'an, and just 19 days after Emperor Taizong took the throne, the two khans were just across the Wei River from Chang'an. Emperor Taizong, accompanied by Gao Shilian and Fang Xuanling, was forced to meet Ashina Duobi across the river and personally negotiate peace terms, including tributes to Eastern Turks, before Ashina Duobi withdrew.