William Harrison Hays Sr. (; November 5, 1879 – March 7, 1954) was an American politician, and member of the Republican Party. As chairman of the Republican National Committee from 1918–1921, Hays managed the successful 1920 presidential campaign of Warren G. Harding. Harding then appointed Hays to his cabinet as his first Postmaster General. He resigned from the cabinet in 1922 to become the first chairman of the Motion Picture Producers and Distributors of America. As chairman, Hays oversaw the promulgation of the Motion Picture Production Code (informally known as the Hays Code), which spelled out a set of moral guidelines for the self-censorship of content in American cinema.