The district is almost the same as the Prince-Bishopric of Osnabrück which existed until 1803. When the clerical states of Germany were dissolved, Osnabrück became part of the Kingdom of Hanover, which in turn fell to Prussia in 1866. The district was established in 1972 by merging four old districts (Osnabrück, Melle, Bersenbrück, Wittlage).