South Carolina seceded from the Union in late 1860 in reaction to the upward revision of the tariff by the North. election of a Republican candidate as president. northern military attack on Fort Sumter. selection of an antislavery speaker of the House.

election of a Republican candidate as president.

Explanation:

South Carolina was part of the Stated which were in support of the continued slave trade and use in the country. During this period, the Republicans were in support of the abolition of slavery.

President Lincoln who was a republican then became the President and the state of South Carolina knew the slavery would be abolished which made them to secede from the Union in late 1860.