The Republican party grew out of the conflicts regarding the expansion of slavery into the new Western territories. The stimulus for its founding was provided by the passage of the Kansas-Nebraska Act of 1854. That law repealed earlier compromises that had excluded slavery from the territories. The passage of this act served as the unifying agent for abolitionists and split the Democrats and the Whig party. "Anti-Nebraska" protest meetings spread rapidly through the country. Two such meetings were held in Ripon, Wis., on Feb. 28 and Mar. 20, 1854, and were attended by a group of abolitionist Free Soilers, Democrats, and Whigs. They decided to call themselves Republicans-because they professed to be political descendants of Thomas Jefferson's Democratic-Republican party. The name was formally adopted by a state convention held in Jackson, Mich., on July 6, 1854.
The Republican party was a success from the beginning. In the 1854 congressional elections 44 Republicans were elected to the House of Representatives and several were elected to the Senate and various state houses. In 1856, at the first Republican national convention, Sen. John C. Fremont was nominated for the presidency but was defeated by Democrat James Buchanan.
The GOP of the Lincoln era was mostly spawned from the WHIG Party.
Brief history of the Whigs
Four presidents of the United States were members of the Whig Party. Considered integral to the Second Party System and operating from the early 1830s to the mid-1850s,[1] the party was formed in opposition to the policies of President Andrew Jackson and his Democratic Party.In particular, the Whigs supported the supremacy of Congress over the presidency and favored a program of modernization and economic protectionism. This name was chosen to echo the American Whigs of 1776, who fought for independence, and because "Whig" was then a widely recognized label of choice for people who identified as opposing tyranny.[2] The Whig Party counted among its members such national political luminaries as Daniel Webster, William Henry Harrison, and their preeminent leader, Henry Clay of Kentucky. In addition to Harrison, the Whig Party also nominated war hero generals Zachary Taylor and Winfield Scott. Abraham Lincoln was the chief Whig leader in frontier Illinois.
In its two decades of existence, the Whig Party had two of its candidates, William Henry Harrison and Zachary Taylor, elected president. Both died in office. John Tyler succeeded to the presidency after Harrison's death but was expelled from the party. Millard Fillmore, who became president after Taylor's death, was the last Whig to hold the nation's highest office.
The party was ultimately destroyed by the question of whether to allow the expansion of slavery to the territories. With deep fissures in the party on this question, the anti-slavery faction prevented the re-nomination of its own incumbent President Fillmore in the 1852 presidential election; instead, the party nominated General Winfield Scott. Most Whig party leaders thereupon quit politics (as Lincoln did temporarily) or changed parties. The northern voter base mostly joined the new Republican Party. By the 1856 presidential election, the party was virtually defunct. In the South,
Some of you, those with at least a reasonable grasp of the obvious, will note that Thomas JEFFERSON is not mentioned as having anything to do with the Whigs?
But the WHIGS (and then later the Republicans who'd BEEN Whigs) did lay claim to having the same political POV as Jefferson.
However Jefferson never heard of the Republicans, he founded the Democrttic Republican party
The Democratic-Republican Party was the political party organized by Thomas Jefferson and James Madison in 1791-93. It stood in opposition to the Federalist Party and controlled the Presidency and Congress, and most states, from 1801 to 1824, during the First Party System. It split after the 1824 presidential election into two parties: the Democratic Party and the short-lived National Republican Party (later succeeded by the Whig Party, many of whose adherents eventually founded the modern Republican Party).
Most contemporaries called it the Republican Party. Today, political scientists typically use the hyphenated version while historians usually call it the "Republican Party" or the Jeffersonian Republicans, to distinguish it from the modern Republican Party, which was founded in 1854 and named after Jefferson's party.