At the beginning of World War II, the Italian First Army was one of three armies that made up Army Group West commanded by Prince General Umberto di Savoia. Together with the Italian Fourth Army and the Italian Seventh Army (kept in reserve), the First Army attacked French forces during the Italian invasion of France. At this time, the First Army was commanded by General Pietro Pintor and included three army corps: the 2nd Corps commanded by General Francesco Bettini, the 3rd Corps - General Mario Arisio, and the 15th Corps commanded by General Gastone Gambara. (See order of battle, below.)