Bảo Lạc
Bảo Lạc lies in the mountainous frontier country west of Cao Bằng, among the upper valleys of the Gâm River. The Nông family held hereditary local authority here for generations, governing a land of steep ridges and forested valleys. Its position placed it between the northern Vietnamese plains and the borderlands towards China.
In 1833 Nông Văn Vân, the local chief, defied the Nguyễn court after officials sought to remove him. His rising spread from the mountain frontier to Tuyên Quang, Thái Nguyên, Cao Bằng and Lạng Sơn, drawing support from other local leaders. Nguyễn armies fought the rebels for more than a year before the movement was defeated in 1835. The campaign showed the continuing strength of local chiefly families in the northern highlands.