You had to look up Jim Crow laws? If you are American then that is an active level of ignorance. It is taught in most schools systems as far as I am aware, and is frequently brought up in the news and other political commentary, especially in the context of any sort of checks on voter registration. I took OP's comment as you would have to look up the peonage system

If you are not American then it would be perfectly understandable to be unaware