Massachusetts Republican Party
The Massachusetts Republican Party was founded in 1854. Drawing together abolitionist and nativist anti-Catholic elements, it quickly became the dominant political force in the state and a powerful arm of the national Republican Party. Significant founding figures include Senator Charles Sumner, formerly of the Free Soil Party, and Speaker of the House Nathaniel Prentiss Banks, formerly of the American Party. 
At the time of the Republican Party's founding in 1854, all of Massachusetts's congressional representatives but Sumner were members of the nativist Know-Nothing Party. However, Banks's role as chairman of the 1856 Republican National Convention, his active support for the Republican presidential nominee John C. Frémont in 1856 and his focus on anti-slavery legislation as Speaker put him at odds with his party. Following the Democratic victory in the 1856 elections and the Dred Scott case in 1857, the national American Party organization collapsed, and most Northern members joined the nascent Republicans. In 1857, Banks ran as a Republican against incumbent Know-Nothing Governor Henry J. Gardner and won a decisive victory.
Factions in the Republican Party (United States)
The Radical Republicans were a major factor of the party from its inception in 1854 until the end of the Reconstruction Era in 1877. The Radicals strongly opposed slavery and later advocated equal rights for the freedmen and women. They were often at odds with the moderate and conservative factions of the party. During the American Civil War, Radical Republicans pressed for abolition as a major war aim and they opposed the moderate Reconstruction plans of Abraham Lincoln as too lenient on the Confederates. After the war's end and Lincoln's assassination, the Radicals clashed with Andrew Johnson over Reconstruction policy. After winning major victories in the 1866 congressional elections, the Radicals took over Reconstruction, pushing through new legislation protecting the civil rights of African Americans. They supported Ulysses S. Grant for President in 1868 and 1872. However, their influence waned as Democrats retook control in the South and enthusiasm for continued Reconstruction declined.