the present combined territory of the district and the city of osnabrück is almost identical to the prince-bishopric of osnabrück which existed until 1802, when it was mediatised and assigned to the electorate of hanover. it was occupied by france between 1807 and 1813, after which it was returned to the kingdom of hanover. after the 1866 austro-prussian war, the kingdom of hanover (including the former bishopric of osnabrück) was annexed by prussia. since 1 november 1946, the area is part of lower saxony.