The 75th Reserve Division initially fought on the Eastern Front. Its baptism of fire was in the Second Battle of the Masurian Lakes. It fought along the Narew in July and August 1915 and participated in the conquest of Grodno and the Battle of Vilnius. From October 1915 to August 1916, the division remained in positional warfare and then fought at Kovel. Afterwards, it returned to the trenchlines until late June 1917. The division then fought against the Russian Kerensky Offensive and was part of Oskar von Hutier's Eighth Army in the Battle of Riga in September 1917. In December 1917, the division was transferred to the Western Front and went into the line north of the Ailette, above the Chemin des Dames. It participated in the 1918 German spring offensive, fighting in the Third Battle of the Aisne. It then occupied various parts of the line and fought against the various Allied counteroffensives, ending the war fighting against the Meuse-Argonne Offensive. Allied intelligence rated the division as third class.