United States Marine Corps A decade later, in the Mexican–American War (1846–1848), the Marines made their famed assault on Chapultepec Palace in Mexico City, which would be later celebrated as the "Halls of Montezuma" in the Marines' hymn. In the 1850s, the Marines would see further service in Panama and Asia, attached to Matthew Perry's East India Squadron on its historic trip to the Far East. The Marine Corps played a small role in the Civil War (1861–1865); their most prominent task was blockade duty. As more and more states seceded from the Union, about a third of the Corps' officers left the United
Assistant Commandant of the Marine Corps the Navy – may delegate to or prescribe for him. Orders issued by the Assistant Commandant in performing such duties have the same effect as those issued by the Commandant. When there is a vacancy in the office of Commandant of the Marine Corps, or during the absence or disability of the Commandant, the Assistant Commandant shall perform the duties of the Commandant until a successor is appointed or the absence or disability ceases. ! # ! class="unsortable"|Photo ! Rank ! Name ! Tenure from ! Tenure to ! Became Commandant Assistant Commandant of the Marine Corps The Assistant Commandant