Why did slavery grow or expand so much in the 1800s

Explanation:

Easily answered! When it was the 1800s people were bringing black people in form all over the place. Most of the time they brought them in from Western Africa. They needed slaves and as much of them as they can get for cotton fields, remember, cotton fields is what helped produce their clothes so they needed as much people as they can get to work in these fields.

yellow fever and other tropical diseases

answer; i believe the above statement is (true);