Gao Pian (822–887), the architect of the medieval citadel of Hanoi and of large-scale defensive and communication works in several frontier regions of China, is a towering figure in the military, political, and intellectual history of both countries. A charismatic governor and commander, inclined to the occult arts of strategy, he was a man of wide learning and curiosity, with a strong attraction to Daoism, as well as a talented poet. In turn reviled and revered, for his pivotal roles in hastening both the end of the Tang and the emergence of Vietnam, Gao Pian became the object of local cults in his own lifetime. The presence of prominent literati on his staff contributed to this renown. At the end of his career, Gao laid the foundations of an independent kingdom in Huainan under the Five Dynasties culmination of regional autonomy in post-An Lushan China.