The Republican Party, also referred to as the “Grand Old Party” or GOP, is one of the world’s oldest extant political parties. The party values reflect economic conservatism, classical conservatism (modern day American conservatism) and corporate liberty rights. It is the second oldest existing political party in the United States after its primary rival, the Democratic Party. The party emerged in 1854 to combat the Kansas–Nebraska Act, an act that dissolved the terms of the Missouri Compromise and allowed slave or free status to be decided in the territories by popular sovereignty. The early Republican Party had almost no presence in the Southern United States, but by 1858 it had enlisted former Whigs and former Free Soil Democrats to form majorities in nearly every Northern state.

With its election of Abraham Lincoln in 1860 and its success in guiding the Union to victory in the American Civil War and abolishing slavery, the party came to dominate the national political scene until 1932. The Republican Party at its beginning consisted of African-American and White Northern Protestants, businessmen, small business owners, professionals, factory workers, and farmers. It was pro-business, supporting banks, the gold standard, railroads and high tariffs to protect factory workers and grow industry faster. Under William McKinley and Theodore Roosevelt, it emphasized an expansive foreign policy.

The GOP lost its majorities during the Great Depression (1929–1940). Instead, the Democrats under Franklin D. Roosevelt formed a winning New Deal coalition, which was dominant from 1932 through 1964. That coalition collapsed in the mid-1960s, partly because of White Southern Democrats’ disaffection with the passage of the Civil Rights Act of 1964. Republicans won five of the six presidential elections from 1968 to 1988, with Ronald Reagan as the party’s iconic conservative hero. From 1992 to 2016, the Republican candidate has been elected to the White House in three of the seven presidential elections. Two of these (the 2000 and 2016 elections) saw George W. Bush and Donald Trump losing the popular vote, but winning the Electoral College. A similar situation in which Republicans won the Electoral College, but lost the popular vote were the 1876 and 1888 elections.

The Republican Party expanded its base throughout the South after 1968 (excepting 1976), largely due to its strength among socially conservative white evangelical Protestants and traditionalist Roman Catholics. As white Democrats in the South lost dominance of the Democratic Party once American courts declared the Democratic White Primary Elections unconstitutional, the region began taking on the two-party apparatus which characterized most of the nation. The Republican Party’s transforming leader by 1980 was Reagan, whose conservative policies called for reduced government spending and regulation, lower taxes and a strong anti-Soviet Union foreign policy.

Reagan’s influence upon the party persists as nearly every Republican Party speaker still reveres him. As such, social scientists Theodore Caplow et al. argue: “The Republican party, nationally, moved from right-center toward the center in the 1940s and 1950s, then moved right again in the 1970s and 1980s”