A short lived but interesting political party
that coalesced out of the belief
that the expansion
into the Western territories was a very bad idea.
This was partially inspired by the Wilmot Proviso
One important thing to note about this party is that they were not implicitly against slavery as a moral crime but more as bad economic policy. The slogan was "Free soil, free speech, free labor, free men." They were largely supported by people who would benefit economically from the freezing of slave labor in the new territories.
The first nominee on the Free-Soil ticket was Martin Van Buren. The practical effect of their bid was that it weakened the Democrats and gave the Whig candidate Zachary Taylor the push he needed to get elected. The one coup for the Free-Soilers was holding the balance of power in the House of Representatives.
The life span of the Free-Soil Party was only about six years and it came unraveled in the end with members bickering about the morality of slavery and duty to the Southern states to keep things as they were.
Eventually many of the Free-Soilers formed the Republican Party which considered slavery morally wrong as well and were much more influential in legislation limited slavery.