What political party dominated the south during the antebellum period?

The Democratic Party.

Explanation:

The antebellum period is after the War of 1812, and before the Civil War. This was before the party switch. 2 parties dominated the politcal landscape during this time, they were the Democratic and Republican parties. The Republicans were anti-slavery, which is not what the south wanted, so they supported the Democrats.

inflamed public's opinion against the britain