The division was mobilized as the 7th Infantry Division in August 1914 and sent to the west for the opening campaigns of the war. It fought in the siege of the Belgian fortifications at Liège, and then participated in the subsequent march into France and the Race to the Sea. The division then spent time in the trenches, and fought in the Battle of the Somme in 1916. During the German spring offensive of 1918, the division fought in the Battle of the Lys. It then fought in the defensive battles against the Allied offensives, including the Hundred Days Offensive and the Meuse-Argonne Offensive. The division was rated a first-class division by Allied intelligence.