He was commissioned a first lieutenant in the Marine Corps on 8 April 1899; promoted to captain, 23 July 1900; to major, 13 May 1908; to lieutenant colonel, 1 August 1916; to colonel (temporary), 1 July 1918; to brigadier general (temporary), 7 October 1918; to colonel (permanent), 9 March 1919; to brigadier general (permanent), 4 June 1920; and to major general, 5 July 1929.
In April 1899, 1stLt Butler was assigned to duty with the Marine Battalion at Manila, Philippine Islands. From 14 June to October 1900, he served with distinction in China, and was promoted to captain by brevet for distinguished conduct and public service in the presence of the enemy near Tientsin, China. He was wounded in that battle on 13 July 1900.
His first Medal of Honor was presented following action at Vera Cruz, Mexico, 21-22 April 1914, where he commanded the Marines who landed and occupied the city. Maj Butler "was eminent and conspicuous in command of his Battalion. He exhibited courage and skill in leading his men through the action of the 22nd and in the final occupation of the city."
The following year, he was awarded the second Medal of Honor for bravery and forceful leadership as Commanding Officer of detachments of Marines and seamen of the USS Connecticut in repulsing Caco resistance on Fort Riviere, Haiti, 17 November 1915.
During World War I, he commanded the 13th Regiment in France. For exceptionally meritorious service, he was awarded the Army Distinguished Service Medal, the Navy Distinguished Service Medal, and the French Order of the Black Star. When he returned to the United States in 1919, he became Commanding General of the Marine Barracks, Quantico, Virginia, and served in this capacity until January 1924, when he was granted leave of absence to accept the post of Director of Public Safety of the City of Philadelphia. In February 1926, he assumed command of the Marine Corps Base at San Diego, California. In March 1927, he returned to China for duty with the 3d Marine Brigade. From April to 31 October he again commanded the Marine Barracks at Quantico. On 1 October 1931, he was retired upon his own application after completion of 33 years' service in the Marine Corps.