It all started in this little white schoolhouse in Wisconsin.

In Ripon, Wisconsin, former members of the Whig Party met to
establish a new party to oppose the spread of slavery into the
western territories. The Whig Party, which was formed in 1834
to oppose the “tyranny” of President Andrew Jackson, had
shown itself incapable of coping with the national crisis over
slavery.

With the successful introduction of the Kansas-Nebraska Bill
of 1854 that dissolved the terms of the Missouri Compromise
and allowed slave or free status to be decided in the territories
by popular sovereignty, the Whigs disintegrated.

By February 1854, anti-slavery Whigs had begun meeting in the
upper midwestern states to discuss the formation of a new party
and one such meeting, in Wisconsin was on this day in 1854 and
is generally remembered as the birth of the Republican Party.