What political party was split on the issue of slavery which eventually cause the party to collapse?

The Whig Party was split on the issue of slavery, which ultimately led to its collapse in the 1850s. The internal divisions arose primarily over the expansion of slavery into new territories and states, causing a rift between Northern Whigs who opposed slavery and Southern Whigs who supported it. This fracture contributed to the rise of the Republican Party, which united anti-slavery factions and absorbed many former Whigs.