Ostrobothnia (historical province)

Ostrobothnia
Historical province of Ostrobothnia in blue (including the historical Västerbotten) and modern regions of Finland in yellow
Country Finland
 Sweden (before 1809)
RegionsSouthern Lapland
Kainuu
North Ostrobothnia
Central Ostrobothnia
Ostrobothnia (administrative region)
South Ostrobothnia

Ostrobothnia (Swedish: Österbotten; Finnish: Pohjanmaa) is a historical province comprising a large portion of western and northern Finland. Before the Treaty of Fredrikshamn in 1809, Ostrobothnia was part of Sweden. It is bounded by Karelia, Savo, Tavastia (Häme) and Satakunta in the south, the Bothnian Sea, Bothnian Bay and Swedish Norrbotten in the west, Lapland in the north and Russia in the east.