William H. Seward
The Republican Party had been founded in 1854, in reaction to the Kansas-Nebraska Act. Its anti-slavery stance was attractive to Seward, but he needed the Whig structure in New York to get re-elected. In September 1855, the New York Whig and Republican parties held simultaneous conventions that quickly merged into one. Seward was the most prominent figure to join the new party, and was spoken of as a possible presidential candidate in 1856. Weed, however, did not feel that the new party was strong enough on a national level to secure the presidency, and advised Seward to wait until 1860. When Seward's name was mentioned at the 1856 Republican National Convention, a huge ovation broke out. In the 1856 presidential election, the Democratic candidate, former Pennsylvania senator James Buchanan, defeated the Republican, former California senator John C. Frémont, and the Know Nothing candidate, former president Fillmore.
Liberal Republican Party (United States)
Originally liberal republicans advocated for a return to traditional classical republicanism, and were concerned about corruption and centralized power creeping into the Federal government and they wanted to reform the Republican party. As the liberal republicans began to form a political party, a few years later, it was taken over by others who were anti-Grant and anti-reconstruction. 
The party began in Missouri in 1870 under the leadership of Carl Schurz and spread nationwide. It had strong support from powerful Republican newspaper editors such as Murat Halstead of the "Cincinnati Commercial", Horace White of the "Chicago Tribune", Henry Watterson of the "Louisville Courier-Journal", Samuel Bowles of the "Springfield Republican" and especially Whitelaw Reid and Horace Greeley of the "New-York Tribune". Many Liberal Republican leaders had been Democrats and members of the Free Soil Party before joining the Republican Party after its creation in the 1850s.