William Morris was born in the Ocean Grove section of Neptune Township, New Jersey, on March 22, 1890.

He graduated from there in June 1911, alongside John P. Lucas, Frederick Gilbreath, Charles P. Hall, Joseph Cowles Mehaffey, John R. Homer, Karl Slaughter Bradford, Thompson Lawrence, Jesse A. Ladd, Gustave H. Franke, James R.N.

Weaver, Paul W. Baade, Herbert Dargue, Alexander Surles, Harold F. Nichols, Raymond Albert Wheeler, Philip Bracken Fleming, Ira T. Wyche.

In July 1918 he was sent to the Western Front and was appointed commanding officer (CO) of the 1st Battalion, 360th Infantry Regiment, part of the 90th Division of the American Expeditionary Force (AEF).

He remained in Europe with the Army of occupation, commanding his battalion in Germany, and then serving on the staffs of the (AEF) General Headquarters (GHQ) and the IX Corps.

[1] After the war Morris returned to the United States in June 1919 as a ROTC instructor at Bucknell University, Pennsylvania, where he was a professor of Military Science and Tactics.

He entered the U.S. Army Command and General Staff School at Fort Leavenworth, Kansas in 1924, and graduated from there in 1925.

After he graduated he served as a staff officer with the HQ of the 8th Coast Artillery Regiment, then stationed at Fort Sam Houston, Texas.

Upon hearing of the death of Major General Paul Newgarden, CG of the 10th Armored Division, who died in a plane accident, in July 1944, he contacted General George C. Marshall, the U.S. Army Chief of Staff, and requested demotion to command of the 10th Armored Division, then preparing for transfer to the European Theater of Operations (ETO).