No less than in modern times, law under imperial systems can do many things. Its enactment can be a focus for bureaucratic debate and struggle. Its implementation may provoke bitter resistance or creative adaptations. It can be ignored or it can spur unpredictable social change. In eighteenth-century southwestern China, law did all this: issues of law are paramount in the burst of Qing (1644–1911) expansion and Han Chinese colonization which brought many local non-Han societies directly under imperial governance for the first time. This paper examines both its development and its effects in the remote region of the Eastern Miao (Hmong) (see map), a group based on settled agriculture in the Hunan/Guizhou provincial border zone west of the Yuan river. It begins with administrative incorporation (which occurred in two stages in 1703–4 and 1727–32) and ends on the eve of the Miao uprising and its suppression in the 1790s.