In World War I in 1914, the 20th Infantry Division fought in the Allied Great Retreat, including the First Battle of the Marne

21 Infantry Div + 81st Infantry Regiment in World War I, 1914

Königlich Preußische 21. Infanterie-Division

The 21st Division (21. Division) was a unit of the Prussian/German Army. It was formed on October 11, 1866 and was headquartered in Frankfurt am Main. The division was subordinated in peacetime initially to the XI Army Corps (XI. Armeekorps) and from 1899 to the XVIII Army Corps (XVIII. Armeekorps).

Königlich Preußisches Infanterie-Regiment Landgraf Friedrich I. von Hessen-Cassel
(1. Kurhessisches) Nr.81

The Royal Prussian Infantry Regiment Frederick I, Landgrave of Hesse - Kassel (1. Kurhessisches) No. 81was formed in 1700 as the regiment 'Prince Anhalt' and its first Commander was Oberst Kurt von Uffeln. The Regiment fought in various conflicts on the European mainland, the United Kingdom and the American continent. After WW1 the Regiment became 'tradition company' Nr 10 of the 15th Infantry Regiment of the Reichswehr. The 15th Regiment was destroyed during the Battle of Stalingrad.