The Poznan Army was a formation of the Polish Army that existed from 23 March to 21 September 1939. The army was created with the goal of protecting Poznan and Wielkopolska in the case of a German invasion, and it bordered the Pomorze Army's territory to the north and the Lodz Army to the south. In September 1939, the army was destroyed at the Battle of the Bzura, and its remnants surrendered after the fall of Warsaw.