King was born in Bridgewater, Massachusetts in 1873 and entered the United States Military Academy (USMA) at West Point, New York in 1892.

[1] Football historian Parke H. Davis later wrote of King: Of his foot ball days he is remembered as a swift, elusive, crashing and flashing back; courageous, tenacious and chivalrous; a true soldier of the gridiron as he was of the real battle-fields.

[1]Among his classmates there were several men who would, like King himself, eventually attain the rank of general officer, such as Merch Bradt Stewart, Lucius Roy Holbrook, Dennis E. Nolan, Frank C. Bolles, LeRoy Eltinge and George Henry Shelton.

His great personal bravery in disarming a hostile Filipino saved the life of a brother officer.

[2]In 1903, King returned to West Point and served one year as the head coach of the Army football team.

After the season, he agreed to serve as head coach for the academy's ice hockey team in its inaugural year.

He was the Chief of Staff of the 28th Division, a National Guard formation known as the "Keystoners," in Camp Hancock, Georgia, and also during part of its campaign in France.

[2] He remained with the Army of Occupation in Luxemburg from December 1918, a month after the Armistice with Germany which ended hostilities, until April 1919 and returned to the United States in 1919.