Walter Sweeney was born on July 23, 1909, in Wheeling, West Virginia. He entered the U.S. Military Academy at West Point on July 23, 1926, and was commissioned a 2d Lt of Infantry on June 12, 1930. Lt Sweeney served with the 29th Infantry at Fort Benning, Georgia, from July 1930 to October 1934, and then attended flying school from October 1934 to October 1935. Lt Sweeney was awarded his pilot wings at Randolph Field, Texas, in October 1935, and then attended the attack course at Kelly Field, Texas, from October 1935 to May 1936. His next assignment was as as a pilot with the 8th Attack Squadron of the 3rd Attack Group at Barksdale Field, Louisiana, from June 1936 to June 1939, followed by service at Hickam Field, Hawaii, where he served with the 431st Bomb Squadron, 31st Bomb Squadron, 50th Reconnaissance Squadron, and 11th Bomb Group from June 1939 to June 1942. Col Sweeney next served on the War Department General Staff in Washington, D.C., from July 1942 to July 1944, and then as Chief of Staff and later as Deputy Commander for the 73rd Bomb Wing in the Pacific Theater from July 1944 to July 1945. His next assignment was on the staff of the Strategic Air Force, Pacific Ocean Area, on Guam from July 1945 to January 1946, followed by service on the Joint War Plans Committee for the Army Air Forces in Washington, D.C., from January to July 1946. Col Sweeney served as an instructor at the National War College from July 1946 to October 1947, and then served in the Office of the Assistant Secretary of the Air Force from October 1947 to October 1948. Gen Sweeney then served as Director of Plans with Headquarters Strategic Air Command at Offutt AFB, Nebraska, from October 1948 to April 1953, followed by service as Commander of 15th Air Force at March AFB, California, from April 1953 to July 1955. He was Commander of 8th Air Force at Westover AFB, Massachusetts, from August 1955 to October 1961, and then served as Commander-in-Chief of Tactical Air Command at Langley AFB, Virginia, from October 1961 until his retirement from the Air Force on August 1, 1965. Walter Sweeney died on December 22, 1965.

His Distinguished Service Cross Citation reads:

For extraordinary heroism in connection with military operations against an armed enemy while serving as Pilot of a B-17 Heavy Bomber and Commander of the 431st Bombardment Squadron, 11th Bombardment Group (H), HAWAIIAN Air Force. Colonel Sweeney led his squadron in action at Midway Island against the Japanese Fleet from 3 to 6 June 1942, being opposed by enemy aircraft and anti-aircraft fire which demanded the highest type of courage. The extraordinary leadership and zealous devotion to duty displayed by Lieutenant Colonel Sweeney have upheld the highest traditions of the military service and reflect great credit upon himself, the Hawaiian Air Force, and the United States Army Air Forces.