Gallwitz grew up in a
Catholic family in Breslau and joined the Prussian Army in 1870. In 1891, he married Friedrike. They had a daughter and son Werner, who became a lieutenant general in the
Second World War. Gallwitz was a First World War corps commander (
Guards Reserve Corps) on the Western Front, but he was almost immediately transferred east to join the
Eighth Army under
Hindenburg. (later redesignated
Twelfth Army) and participated in the Galicia offensive alongside
Mackensen, who commanded the
Eleventh Army. Towards the end of 1915, Gallwitz succeeded Mackensen as commander of the Eleventh Army, as the latter campaigned against
Serbia. In 1916, he moved back to the Western Front and defended against the British attack in the
Battle of the Somme. He took over command of
2nd Army and of
Heeresgruppe Gallwitz – Somme controlling the
1st and 2nd Armies. From 1916–18, he commanded the
Fifth Army in the west, most notably engaging the Americans during the
Battle of Saint-Mihiel. Following his retirement from the army, Gallwitz served as a deputy in the
Reichstag (1920–24) for the
German National People's Party. ==Awards and decorations==