That part of a country which lies on the limit of the settled area; the term indicates outward expansion into an area previously unsettled by a particular state. ‘The frontier arrives and passes, in a historical sense, replacing one set of social relations with another’ (Simmons et al. (2007) AAAG 97, 3). Some frontiers have occurred where two nations advance from different directions, leading to boundary disputes. A settlement frontier marks the furthest advance of settlement within a state while the political frontier is where the limit of the state coincides with the limit of settlement.

Jepson (2006) Econ. Geog. 82, 3 links the agricultural frontier with land rents, transportation costs, and the institution of private property; the fringe of market-oriented agriculture and ranching, which advances on subsistence farming or uncultivated wilderness, as the case may be. See also Rindfuss et al. (2007) AAAG 97, 4 on land change in agricultural frontiers. Pallot (2005) TIBG 30, 1 sees the Soviet use of the peripheries as a place of exile as driven by a powerful state intent on expanding the resource frontier; see also Hanlon and Halseth (2005) Canad. Geogr./Géogr. canad. 49, 1 on the greying of resource communities in northern British Columbia. Davidson (2007) TIBG 32, 4 and Butler and Lees (2006) TIBG 31, 4 write on gentrification frontiers.