Stevenson served as an apprentice seaman in the U. S. Naval Reserves in 1916. After the war he went to school, graduating from Princeton in 1922 and from Harvard Law School in 1926. He was the grandson of a former vice president.

Stevenson practiced law in Chicago, as special counsel for the A.A.A., and was appointed Federal Alcohol Administrator in 1934. He was a special assistant Secretary of the Navy, 1941-1944.

In 1943, he was sent on a mission to Italy and in 1944 on an Air Force mission to Europe. He was a member of the U. S. Delegation to the United Nations in 1946, and was later elected Governor of Illinois where he put through a heavy reform program.

In 1952, the Democrat party drafted Stevenson as its candidate for president. After his defeat he became the party leader and received the nomination again in 1956, losing a second time. Many influential friends tried valiantly to obtain nomination for him again in 1960, but were unsuccessful, the careful preparations made by and on behalf of John F. Kennedy prevailing.

Stevenson favored repeal of the Taft-Hartley Act and was endorsed by leaders of the C.I.O. and the A.F. of L. in his campaigns. He continued to work with the United Nations, representing the United States in that body.