Final answer:
The Free Soil Party was a strong antislavery group in the 1850s, which eventually merged with others to form the Republican Party. This transition significantly impacted the political dynamics in the pre-Civil War era.
Step-by-step explanation:
In the 1850s, the Free Soil Party was a strong antislavery group that would join other small coalitions and a faction of Whig members to form the Republican Party. The Free Soil Party was significant because it was directly opposed to the expansion of slavery into new territories. After the dissolution of the Whig party, many of its members, along with antislavery Democrats, joined the Free Soil Party. They all came together to form the Republican Party in 1854, a political organization that championed the cause of stopping the spread of slavery. This crucial development reshaped the political landscape of the United States deeply ingrained in the pre-Civil War era.
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