On October 8, 1918, the regiment began participation in one of the great chapters in its combat history, the Meuse-Argonne campaign. On that day, along a line extending four kilometers east to west, the 141st and 142d regiments attacked German positions, resulting in a "substantial gain of ground" but suffering casualties to sixty-six officers and 1,227 enlisted men. After being relieved by the 72d Brigade (143rd and 144 Inf), the unit side-stepped to take a place at the east end of the line of the 72d Brigade several days later. On October 27, the unit took part in the assault on "Foret (Forest) Farm", and then was relieved on October 28, taking no further combat action in the war. The unit returned to the United States after six additional months in France and was mustered out July 3, 1919.