In which region did cotton expand most the upper south or the Deep South?

Cotton transformed the United States, making fertile land in the Deep South, from Georgia to Texas, extraordinarily valuable. Growing more cotton meant an increased demand for slaves. Slaves in the Upper South became incredibly more valuable as commodities because of this demand for them in the Deep South.

Upper south

Explanation:

The lower south is full of swamps and marshs, but the upper south is the perfect place for cotton.