United States Marine Corps served as a convenient resource for interventions and landings to protect American interests overseas. The Corps was involved in over 28 separate interventions in the 30 years from the end of the American Civil War to the end of 19th century. They would be called upon to stem political and labor unrest within the United States. Under Commandant Jacob Zeilin's tenure, Marine customs and traditions took shape: the Corps adopted the Marine Corps emblem on 19 November 1868. It was during this time that "The Marines' Hymn" was first heard. Around 1883, the Marines adopted their current motto ""Semper Fidelis""
Sergeant Major of the Marine Corps Sergeant Major of the Marine Corps Sergeant Major of the Marine Corps (officially abbreviated to SMMC<ref name="ALMAR 016/09"></ref>) is a billet, as well as a unique enlisted grade of rank, with a unique non-commissioned grade of rank insignia, in the United States Marine Corps. In the U.S. Marine Corps, sergeant major is the ninth and highest enlisted rank, just above first sergeant, and equal in grade to master gunnery sergeant, although the two have different responsibilities. A sergeant major typically serves as the unit commander's senior enlisted adviser and to handle matters of discipline and morale among the enlisted Marines.