The Sixth Marines was first organized in Quantico, Virginia on 11 July 1917. In June 1918, the Regiment, together with the Fifth Marines and Sixth Machinegun Battalion launched the famous attack against the German Forces entrenched in Belleau Wood. In recognition of the "Brilliant courage, vigor, spirit, and tenacity of the Marines," the French Government awarded them a citation of the Croix de Guerre with Palms. Late, for heroic action in the Soisson and Champagne Sectors, the Marines were twice cited for their valor in battle. As a result of these actions, the Sixth Marine Regiment was awarded the Fourragere. With the signing of the armistice ending World War I in November 1918, the Sixth Marines continued to serve as part of the Occupational Forces in Germany.
Activated 14 August 1917 at Quantico, Virginia as the 3rd Battalion, 6th Regiment. Deployed during October-November 1917 to France and assigned to the 4th Brigade, American Expeditionary Force. Participated in the following World War I offensive campaigns: Aisne, Aisne-Marne, St. Mihiel, Meuse-Argonne. Participated in the following World War I defensive campaigns: Toulon-Troyon, Chateau-Thiery, Marabache, and Limey. Participated in the occupation of the Rhineland, December 1918-July 1919. Returned during July-August 1919 to Quantico, Virginia. Deactivated 20 August 1919.
During World War 1 the Fifth and Sixth Marines fighting in France as the Fourth Marine Brigade of the Army's Second Division were forced to wear the Army's uniform. The Marines had only the eagle, globe, and anchor on their soft covers to distinguish themselves from their Army brothers in arms. As this did not sit well with the Marines, a patch was designed to distinguish them from their counterparts. A black shield with one five-pointed star and an Indian head with full war bonnet was selected. It is said that the black was for mourning and respect for their casualties, the shield for defense, and the star for the Second Division Commander, Brigadier General John A. Lejeune, and the Indian for General Lejeune's nickname "Old Indian." Another source says the patch was derived from a U.S. Coin in circulation at the time.




