Republican Party (United States)
Founded in 1854, the GOP originally subscribed to classical liberalism and took ideological stands that were anti-slavery and pro-economic reform. Abraham Lincoln was the first Republican president in the history of the United States. The party was usually dominant over the Democrats during the Third Party System and Fourth Party System. In 1912, Theodore Roosevelt formed the Progressive ("Bull Moose") Party after being rejected by the GOP and ran as a third-party presidential candidate. Roosevelt called for many social reforms, some of which were later championed by New Deal Democrats in the 1930s. He lost the 1912 election, and when most of his supporters returned to the GOP, they were at odds with the party's new conservative economic stance; many left for the Democratic Party, and an ideological shift to the right occurred in the Republican Party. Later in the 20th century, the liberal Republican element was overwhelmed by a conservative surge begun by Barry Goldwater in 1964 and continued during the Reagan Era.
Ulster Unionist Party
The Ulster Unionist Party traces its formal existence back to the foundation of the Ulster Unionist Council in 1905. Before that, however, there had been a less formally organised Irish Unionist Alliance (IUA) since the late 19th century, usually dominated by unionists from Ulster. Modern organised unionism properly emerged after William Ewart Gladstone's introduction in 1886 of the first of three Home Rule Bills in response to demands by the Irish Parliamentary Party. The IUA was an alliance of Irish Conservatives and Liberal Unionists, the latter having split from the Liberal Party over the issue of home rule. It was the merger of these two parties in 1912 that gave rise to the current name of the Conservative and Unionist Party, to which the UUP was formally linked (to varying degrees) until 1985.