Background: Holland Smith was born on April 20, 1882 in Hatchechubbee, Alabama to John V. Smith and his wife Cornelia Caroline McTyeire. He received a Bachelor of Science degree from Auburn University (then known as Alabama Polytechnic Institute) in 1901. He had already decided on a military career and had become first sergeant of a cavalry company in the Alabama National Guard. However, he obtained his Bachelor of Laws degree from the University of Alabama in 1903 and practiced law in Montgomery, Alabama for a year.
Context: Returning to the United States in April 1919, Smith's assignments in the next four years included duty at Norfolk, Virginia, study at the Naval War College, Newport, Rhode Island, and service in Washington, D.C., with the War Plans Section of the Office of Naval Operations. There, he was the first Marine officer to serve on the Joint Army-Navy Planning Committee. Leaving Washington in May 1923, he served aboard the battleships Wyoming and Arkansas as Fleet Marine Officer, U.S. Scouting Fleet, until September of that year.  In February 1924, after serving at Marine Corps Headquarters and in the West Indies in connection with joint Army-Navy maneuvers, Smith joined the Marine Brigade on expeditionary duty in Haiti, serving as that unit's Chief of Staff and Officer in Charge of Operations and Training. He returned from that country in August 1925, to serve as chief of staff of the 1st Marine Brigade at Quantico, Virginia, until September 1926, as a student in the Marine Corps School, Quantico, from then until June 1927, and as Post Quartermaster of the Marine Barracks, Philadelphia Navy Yard, from July 1927 to March 1931.  In April 1931, Smith began another tour of sea duty, this time aboard the USS California as Aide to the Commander and Force Marine Officer of the Battle Force, U.S. Fleet. He served in those capacities until June 1933, commanded the Marine Barracks at the Washington Navy Yard from then until January 1935, and served the following two years at San Francisco, California, as chief of staff, Department of the Pacific. From there he was ordered to Marine Corps Headquarters in March 1937, to serve two years as director of the Division of Operations and Training, after which he was Assistant Commandant of the Marine Corps under Major General Thomas Holcomb from April to September 1939.
Question: How long did he serve?. Whats the answer?
Leaving Washington in May 1923, he served aboard the battleships Wyoming and Arkansas as Fleet Marine Officer, U.S. Scouting Fleet, until September of that year.