Upon retirement from the Army in 1946, then President of the United States Harry S. Truman appointed him head of the War Assets Administration.

[1] He attended Clemson Agricultural College for a year,[2][3] before entering the United States Military Academy at West Point, New York, on 2 March 1908.

Several of his fellow graduates would, like Littlejohn himself, eventually attain general officer rank, such as Walter M. Robertson, William H. Wilbur, Walton Walker, John Shirley Wood, Franklin C. Sibert, Harry J. Malony, Stephen J. Chamberlin, Raymond O. Barton and Gilbert R. Cook.

[6] On 5 May 1918, he was posted to the 18th Machine Gun Battalion of the 6th Division at Camp Wadsworth, South Carolina, with the rank of major from 7 June 1918.

[2] The 332nd Machine Gun Battalion moved to France in September 1918, where it joined the American Expeditionary Force (AEF) on the Western Front but did not see action before the armistice.

[4][6] From 28 July 1919 to 1 February 1920, Littlejohn was stationed in Raleigh, North Carolina, as Assistant District Inspector of the Reserve Officers' Training Corps.

On 1 August he was assigned to the Quartermaster of the Fourth Corps Area which replaced the Southeastern Department and soon moved to Fort McPherson, Georgia.

[11] For his services as Quartermaster General, Littlejohn was awarded the Army Distinguished Service Medal with a Bronze Oak Leaf Cluster, the Legion of Merit,[14] the Bronze Star Medal,[2] and foreign awards that included the British Order of the Bath, French Croix de Guerre and Dutch Order of Orange Nassau.

By his broad experience, foresight and splendid ability which was largely instrumental under his leadership in solving many complex questions in organization and supply of the African Task Force.

His untiring efforts and devotion to duty in this connection contributed markedly to the successful landing of this force in North Africa on November 8, 1942.

[16] However Littlejohn was severely criticised when winter clothing was not delivered in a timely manner, resulting in thousands of cases of trench foot and frostbite.

[11] President of the United States Harry S. Truman appointed him head of the War Assets Administration (WAA), which had the responsibility for the disposal of some $34 billion worth of surplus government property.

He disliked the series of monographs written on Quartermaster operations in the ETO by historians at Fort Lee, Virginia, and attacked Roland Ruppenthal's magisterial two-volume Logistic Support of the Armies (1953 and 1959) in the United States Army in World War II series as a slanderous attack on his reputation.