[1] In 1917, Churchill served on the general staff of the American Expeditionary Force in France.

On 5 June 1918, Brigadier General Churchill succeeded Ralph Van Deman as head of the Military Intelligence Branch of the War Department, where he remained until 19 August 1920.

[1] In this capacity, Churchill advocated in December 1918 that MI-8, Cipher Bureau, then headed by Herbert Yardley, continue to do its cryptanalyic work after World War I.

[3] The citation for the medal reads: The President of the United States of America, authorized by Act of Congress, July 9, 1918, takes pleasure in presenting the Army Distinguished Service Medal to Brigadier General Marlborough Churchill, United States Army, for exceptionally meritorious and distinguished services to the Government of the United States, in a duty of great responsibility during World War I as Chief of Staff of the Army Artillery of the 1st Army, American Expeditionary Forces, and for his ability, zeal, and untiring energy in building up the Military Intelligence Division of the General Staff as Director of Military Intelligence.

General Churchill discharged these duties of great responsibility with ability, tact, and energy.