Armee) was a German field army that fought during World War II.

The 3rd Army was activated on September 1, 1939, the day German forces invaded Poland.

The 4th Army was to capture the Polish Corridor and enter East Prussia, thus re-linking the two areas.

The Red Army had attacked Poland from the east with a million men and advanced westwards to meet with the German troops, despite casualties that numbered more than expected.

He stayed in that position until 1942, when he became commander of Army Group North to lead the Siege on Leningrad.