North Petherwin is a rural parish which has transferred between Devon and Cornwall in the past. Until 1844 it was part of Cornwall. In that year it was transferred to Devon but continued to be part of the Launceston Poor Law Union and Rural Sanitary District. In 1894 the rural sanitary district was replaced by the Broadwoodwidger Rural District in Devon and the Launceston Rural District in Cornwall. North Petherwin was considered part of the Broadwoodwidger District, along with two other civil parishes west of the River Tamar. In 1966 this salient was transferred back to Cornwall and North Petherwin became part of the Launceston Rural District until municipal reorganization of 1974. It continues to be part of Cornwall which is now a unitary authority.
Historically, the Dukes of Bedford have been major land owners in the parish. As well as the church town, settlements include Hellescott, Brassacott, and Maxworthy.
Additional source: A Vision of Britain through Time