Warren Gamaliel Harding (November 2, 1865 – August 2, 1923) was the 29th president of the United States, serving from 1921 until his death in 1923. A member of the Republican Party, he was one of the most popular presidents at the time of his death. After that, a number of scandals were exposed that greatly damaged his reputation.

Harding lived in rural Ohio all his life, except when political service took him elsewhere. As a young man, he bought The Marion Star and built it into a successful newspaper. Harding served in the Ohio State Senate from 1900 to 1904, and was lieutenant governor for two years. He was defeated for governor in 1910, but was elected to the United States Senate in 1914—the state's first direct election for that office. Harding ran for the Republican nomination for president in 1920, but was considered a long shot before the convention. When the leading candidates could not garner a majority, and the convention deadlocked, support for Harding increased, and he was nominated on the tenth ballot. He conducted a front porch campaign, remaining mostly in Marion and allowing people to come to him. He promised a return to normalcy of the pre–World War I period, and defeated Democratic nominee James M. Cox in a landslide to become the first sitting senator elected president.

Harding appointed a number of respected figures to his cabinet, including Andrew Mellon at Treasury, Herbert Hoover at Commerce, and Charles Evans Hughes at the State Department. A major foreign policy achievement came with the Washington Naval Conference of 1921–1922, in which the world's major naval powers agreed on a naval limitations program that lasted a decade. Harding released political prisoners who had been arrested for their opposition to World War I. In 1923, Harding died of a heart attack in San Francisco while on a western tour, and was succeeded by Vice President Calvin Coolidge.

The exposure of scandals after Harding's death, including Teapot Dome, as well as an extramarital affair with Nan Britton, eroded his popularity. His interior secretary, Albert B. Fall, and his attorney general, Harry Daugherty, were each later tried for corruption in office; Fall was convicted and Daugherty was not. These trials greatly damaged Harding's posthumous reputation. In historical rankings of U.S. presidents during the decades after his term in office, Harding was often rated among the worst. In the subsequent decades, some historians have begun to reassess Harding's historical record in office.