Which section of the United States relied on slavery as a way to make economic profit ?

Slavery was so profitable, it sprouted more millionaires per capita in the Mississippi River valley than anywhere in the nation. With cash crops of tobacco, cotton and sugar cane, America's southern states became the economic engine of the burgeoning nation.

Explanation: Hope this helps :)

the  wilmot proviso  was designed to eliminate  slavery  within the  landacquired as a result of the mexican war (1846-48). fearing the addition of a pro-slave territory, pennsylvania congressman david  wilmot proposedhis amendment to the bill.