United States Navy Mexican 1911-17 Service Medal. Numbered on rim 8393. Split broach pin attachment system. Very heavily worn condition original ribbon. The Mexican Service Medal awarded by the Army was established by General Orders of the US War Department in December of 1917. The Navy’s Mexican Service Medal was established by Navy Department General Orders Number 365 in February of 1918, as amended by Navy Department General Orders No. 464 in April of 1919. The Mexican Service Medal recognizes those servicemen who performed military service against Mexican forces between April 1911 and June 1919.