How did southern democrats reverse gains made during reconstruction in each of these areas?

Southern Democrats found loopholes in several different laws that allowed them to limit the rights gained by former slaves during the era of Reconstruction.

A perfect example of this would be the requirements/obligations put in place to limit former slaves from voting. This included the development of literacy/citizen tests, poll taxes, and the grandfather clause. The tests given were often near impossible to pass, the poll taxes were ridiculously expensive, and the grandfather clause stopped individuals from voting based on whether or not their grandfather could vote. All of these laws lasted several years before their repeal.