Racism was a big thing in america back in the 1930's. Black people were classed as second class citizens and couldn't walk on the pavement if a white person was. The white people treated them very unfairly what's even worse is the fact that black people had separate areas such as shops and parks etc'.
The only jobs that they could get was to work in the house of white people doing what ever they were asked upon. but they were not allowed to live in there house, they would have to live in a barn or an out building. But this came with concequences like catching deisise, if they spoke to a white women or even looked at one they would get into serious trouble and either get beater or killed.