In mid-1918, Pershing brought Marshall on to the AEF operations staff, G-3, where he worked closely with Pershing and was a key planner of American operations. He was instrumental in the planning and coordination of the Meuse-Argonne Offensive, which contributed to the defeat of the German Army on the Western Front in 1918. Marshall held the permanent rank of captain and the temporary rank of colonel; he was recommended for promotion to temporary brigadier general in October 1918, but the Armistice occurred before the recommendation was acted on. After the war, Marshall reverted to his permanent rank.