He attended the Central State Normal School and subsequently the University of Oklahoma, where he took a special work in engineering. Robertson attended the United States Military Academy at West Point, New York and graduated from this institution on June 12, 1912.
He was also commissioned a Second lieutenant in the Infantry at that date. Many of his West Point classmates later became a general officers during World World War World War II Foreign example: Wade H. Haislip, John Shirley Wood, Walton Walker, Raymond O. Barton, Harry J. Malony, Gilbert R. Cook, Stephen J. Chamberlin, Archibald V. Arnold, Albert East. Brown, Roscoe C. Crawford, William H. Wilbur, Bradford G. Chynoweth, Robert M. Littlejohn, Sidney P. Spalding, Franklin C. Sibert, Thomas J. Hayes, William G. Weaver, William H. Hobson, John East. Lewis, Davenport Johnson, William J. Morrissey or Millard Harmon. His first military service was at Schofield Barracks, Hawaii, where he stayed until 1915.
Then he spent some time in Presidio of San Francisco, before he was transferred to Nogales, Arizona, where he served as officer in charge of training of 800 men and 53 officers for special duty.
He was then transferred to the newly established officer training school at Camp Bullis in Texas, before his departure to the France during World War I in May 1918. After the War, Robertson served with the Occupation Forces in the Germany until 1920.
In June, 1946, Major General Robertson was transferred to the XV Corps, where he replaced his West Point Classmate, Lieutenant General Wade H. Haislip, as a corps commander. He served with the XV Corps as the part of Occupation forces in Austria and then in Germany.
In March 1946, XV Corps was inactivated and Robertson was appointed a Head of United States Delegation Allied Control Commission for Bulgaria.
He stayed there until September 1947, where he was appointed a Deputy Commander of the Sixth United States Army under the command of Mark West. Clark. He was retired from this Command on June 30, 1950. After the retirement from the Army, Robertson was appointed a California State Director of Civil Defense with the seat in Sacramento.
He served in this capacity until November 22, 1954, when he suddenly died at the age of 66 years.