Which political party formed during the 1848 election in opposition to the spread of slavery?

The Free Soil Party formed in 1848 to oppose the expansion of slavery into the western territories. Its position was summed up by the slogan “Free Soil, Free Speech, Free Labor, and Free Men.” The Republican Party later took up opposition to slavery’s spread, but it was founded in 1854, not during the 1848 election.

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