Adlai Ewing Stevenson II (February 5, 1900 – July 14, 1965) was an American politician and diplomat, noted for his intellectual demeanor, eloquent public speaking, and promotion of progressive causes in the Democratic Party. He served as the 31st Governor of Illinois, and received the Democratic Party's nomination for president in 1952 even though he had not campaigned in the primaries. Stevenson was defeated in a landslide by RepublicanDwight Eisenhower in the general election. In 1956 he was again the Democratic presidential nominee against Eisenhower, but was defeated in an even greater landslide. He sought the Democratic presidential nomination for a third time in the 1960, but was defeated by Senator John F. Kennedy of Massachusetts. After his election, President Kennedy appointed Stevenson as Ambassador to the United Nations. He served from 1961 until his death in London from a heart attack.
Governor Adlai Stevenson of Illinois was one of several Democrats who joined the race for the party's presidential nomination after Harry Truman announced in October 1951 that he was not running for a third term. Truman had made this decision as a consequence of the disastrous course of World War III. While Stevenson had a reputation for intelligence and wit, even his fellow Democrats perceived him as being disconnected from the common man.
Stevenson was safely in Illinois the night Soviet Union dropped atomic bombs on Washington, DC in May 1952. Thus, Stevenson was the only Democratic contender to survive the attack and it seemed he would get the nomination by default.