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.
Republicanism in the United States
Modern republicanism is a guiding political philosophy of the United States that has been a major part of American civic thought since its founding. It stresses "liberty" and "unalienable individual rights" as central values, making people sovereign as a whole; rejects monarchy, aristocracy and inherited political power, expects citizens to be virtuous and faithful in their performance of civic duties, and vilifies corruption. American republicanism was articulated and first practiced by the Founding Fathers in the 18th century. For them, "republicanism represented more than a particular form of government. It was a way of life, a core ideology, an uncompromising commitment to liberty, and a total rejection of aristocracy."