Neighbouring districts are Warendorf, Gütersloh, Paderborn, Hochsauerland, Märkischer Kreis, Unna and the independent town of Hamm.
In medieval times Soest was the biggest town in Westphalia; however, after it liberated itself from the bishops of Cologne in the Soester Fehde in 1449 it slowly lost importance, only to gain it again when in 1816 the new Prussian government created the district.
Geographically it covers the northern part of the Sauerland hills and the lower land north of it, the 'Hellweg'.
The rather flat land and very fertile loess soil have made it an agricultural area from ancient times.
After the district was merged with Lippstadt the rose, symbol of the Lippe area, was added on top of the cross.