The Republican Party, commonly referred to as the GOP (abbreviation for Grand Old Party), is one of the two major contemporary political parties in the United States, the other being its historic rival, the Democratic Party. The party is named after republicanism, the dominant value during the American Revolution. It was founded by anti-slavery activists, modernists, ex-Whigs, and ex-Free Soilers in 1854. The Republicans dominated politics nationally and in the majority of northern States for most of the period between 1860 and 1932.
There have been 19 Republican presidents, the first being Abraham Lincoln, who served from 1861 to 1865, when he was assassinated, and the most recent being Donald Trump, who took office on January 20, 2017.
The Republican Party was originally socially liberal, and later, fiscally progressive until Theodore Roosevelt ran for relection in 1912, switching the Democratic and Republican political platforms around and leading to the election of Woodrow Wilson, the first fiscally progressive Democrat.
The Republican Party's current ideology is American conservatism, which contrasts with the Democrats' progressive platform (also called modern liberalism). Further, its platform involves support for free market capitalism, free enterprise, fiscal conservatism, a strong national defense, deregulation, and restrictions on labor unions. In addition to advocating for conservative economic policies, the Republican Party is socially conservative (particularly in its opposition to abortion and same-sex marriage), and seeks to uphold traditional values based largely on Judeo-Christian ethics. Once dominant in the Northeast and Midwest, the party's core support now comes from the South, the Great Plains and the Mountain States, as well as from conservative Catholics,Mormons, and Evangelicals nationwide.