Acording to
The Story of English by Robert McCrum, William Cran, and Robert MacNeil,
Ebonics may have started with pirates, or more accurately with the speech of
18th century sailors. They devote a whole chapter to African American English (my edition of the book was published in 1986, somewhat before the huge Ebonics controversey I remember from the mid '90s) and they treat it as a
creole. They explain that the first European language the African captives heard was probably on board ship on their way to the new world. The crews of most merchant ships at the time spoke
Sabir, which was a mixture of European languages with a very simple
grammar so that
sailors from all over
Europe could communicate. Most Africans brought to the
New World would speak their native language, some Sabir, and some
Portugese.
Although the language that evolved over the following generations was primarily influenced by English, it is interesting to note that some of the same gramatical simplifications which exist in Sabir also exist in Ebonics, so that although I never thought of Pirates and modern speakers of Ebonics as having anything to do with each other, there is a connection.