Morzwiller et Leimbach. On September 1, the regiment returned to Plancher les Mînes and Le Mont while constituted a sapeurs platoon. On September 13, 1915, the Regiment as well as the Moroccan Division () participated to a military inspection revue in presence of the President of the Republic and the Minister of War. During this arms ceremony, the regiment received the regimental colors as well as the Croix de Guerre with palm for the most recent citation at the orders of the armed forces. Combats in the Marne On September 15 and 16, the regiment left Plancher les Mînes for another front zone near Châlons-en-Champagne. The two battalions prepositioned at proximity of Suippes. The 1st Brigade ( Colonel Delavan ) was placed under the authority command of the 10th Colonial Infantry Division () of général Jean-Baptiste Marchand while still remaining though under the authority responsibility of the Moroccan Division. 25 Septembre- Octobre 6 : Second Battle of Champagne On September 25, orders were instructed to take part to the mounted offensive with the 10e DIC in the region of Souain. This offensive went underway until the 28 and resulted in a defeat due to the solid German positions, the incessant bombardments, and the weak artillery preparations. The provisional attempts to take the second German lines on September 28 were unforgiving. Out of the 43 Officers and 1960 men engaged at the front; the regiment endured the loss 20 Officers and 608 men ( killed in action, missing and wounded ). In 4 days of combat, the regiment endured heavy losses while affecting particularly the command corps: both battalion commanders Burel and Declève were killed (or disappeared) and six out eight combat companies lost their Commandants. Total losses for the regiment were 951 men ( Officers : 12 killed or missing, 17 wounded - 922 men killed, missing or wounded ). The regiment was relieved on October 2 and garrisoned on the 4th in camp de la Noblette where a reorganization took place manoeuvering three combat companies per battalion. From October 6 to the 17th, the 2nd Marching Regiment of the 1st Foreign Regiment was engaged again in an operation around Souain. Placed in reserve of armed forces corps, the regiment endured the loss of 115 men ( killed, missing or wounded ) out of which 1 Officer. Dissolution in l'Oise Relieved on October 18, the regiment was in pause at