Harry S. Truman: Harry S. Truman. Self: The History of Sportfishing. Harry S. Truman was the 33rd president of the United States, serving from 1945 to 1953. A lifetime member of the Democratic Party, he previously served as a U.S. senator from the state of Missouri from 1935 to 1945. He was chosen as incumbent president Franklin D. Roosevelt's running mate for the 1944 presidential election. Truman was inaugurated as the 34th vice...