The 22nd Reserve Division began the war on the Western Front. It fought in the opening campaigns against the Belgian Army and the British Expeditionary Force, including the Battle of Mons, and pursued the Allies during the Great Retreat, culminating in the First Battle of the Marne. After 1st Marne, the division held the line between the Aisne and the Oise until the Autumn of 1915, when it went to the Champagne region. In 1916, it fought in the Battle of Verdun. It then saw action in the later phases of the Battle of the Somme. The division occupied various parts of the line in 1917, and then fought in the Battle of Passchendaele. In 1918, it saw action in the German spring offensive, including the Battle of the Lys. Allied intelligence rated the division as second class.