It appears that the present-day form of African American English is not the inheritance of the period of slavery, but the creation of the second half of the 20th century.
“Our achievements speak for themselves. What we have to keep track of are our failures, discouragements and doubts. We tend to forget the past difficulties, the many false starts, and the painful groping.”
“As soon as the harvest is in, you're a migrant worker. Afterwards just a bum.”