By 1915, Bullard was a machine gunner and saw combat on the Somme front in Picardy. In May and June, he was at Artois, and in the fall of that year fought in a second Champagne offensive (September 25 – November 6, 1915) along the Meuse River. He was assigned to the 3rd Marching Regiment of the 1st Foreign Regiment. On July 13, he joined the 2nd Marching Regiment of the 1st Foreign Regiment and also served with the 170th French Infantry Regiment (), known as the ""hirondelles de la mort"" ("swallows of death"). The 2nd Marching Regiment of the 1st Foreign Regiment and the 2nd Marching Regiment of the 2nd Foreign Regiment were serving as part of the 1st Moroccan Division. Commanded initially by Hubert Lyautey, Resident-General of Morocco at the outbreak of World War I, the division was a mix of the Metropolitan and Colonial French troops, including Legionnaires, zouaves and tirailleurs. Towards the end of the war, the 1st Moroccan Division became one of the most decorated units in the French Army. The Foreign Legion suffered high casualties in 1915. It started the year with 21,887 soldiers, NCOs, and officers, but ended with only 10,683. As a result, the Foreign Legion units fighting on the Western front were put in reserve for reinforcement and reorganization. On November 11, 1915, 3,316 survivors from the 1e and the 2e "Etranger" were merged into one unit – the Marching Regiment of the Foreign Legion ("Régiment de Marche de la Légion étrangère"), which in 1920 became the 3rd Foreign Regiment of the French Foreign Legion.