The 1912 Progressive National Convention was held in August 1912. Angered at the renomination of President William Howard Taft over their candidate at the 1912 Republican National Convention, supporters of former President Theodore Roosevelt convened in Chicago and endorsed the formation of a national progressive party. When formally launched later that summer, the new Progressive Party acclaimed Roosevelt as its presidential nominee and Governor Hiram Johnson of California as his vice presidential running mate. When questioned by reporters, Roosevelt said he felt as strong as a "bull moose". Henceforth known as the "Bull Moose Party", the Progressives promised to increase federal regulation and protect the welfare of ordinary people.

The 1912 Republican National Convention was held at the Chicago Coliseum, Chicago, Illinois, from June 18 to June 22, 1912. The party nominated President William H. Taft and Vice President James S. Sherman for re-election for the 1912 United States presidential election.