the district in its present form was established on july 1, 1972 by merging the former districts of melle, bersenbrück and wittlage, and most of the old district of osnabrück. eight municipalities (atter, pye, hellern, nahne, voxtrup, darum, gretesch and lüstringen) were merged with the city of osnabrück in the same year. the former district of osnabrück had already been enlarged with the district of iburg in 1932. the 1972 local government reform also led to a considerable decrease of the number of municipalities.