When the American Expeditionary Force went to Europe, the Army tried to use the Marines solely as labor troops and replacements, but the German spring offensive of 1918 forced the issue for the reluctant General Pershing. Finally getting their chance, the Marines proved themselves at Belleau Wood—and in every well-known AEF action until the end of the war. A collaboration between a French and an American historian, this history traces how the Marine Corps changed from a small organization of naval security detachments to an elite land combat force.