In the process of doing my own genealogical research I've gathered up a significant amount of information about John Adkins. The information Tom provided is consistent with everything I've found thus far. Unfortunately I haven't found any additional information about John's origins. As you may know he is one of the grandparents of William Henry Adkins (born 1850) who is regarded as the first chief of the Chickahominy tribe of Charles City.
My interest in this is that my great-great grandfather was named Oseola Adkins; he was born in 1850, purportedly in Sussex Va. He and his wife (a freed slave) raised my grandmother. She always maintained that Oseola either was a chief or was descended from a line of chiefs / tribal leaders. According to his marriage certificate his father was named Britton Adkins. Below is a link to page at the autry museum which shows the photo of Oseola taken at the Hazel River in Culpeper. Many members of our family still have copies of this photo which were handed down directly by Oseola himself.http://e-humanity.org/artifact.php?artifact_id=15320
My theory is that he and the Adkins of Charles City have some common origins but as yet I've been unable to find them. Tom - do you have any insights on that? Do any of those names ring a bell?
FYI - you might also want to refer to the "Atkins" family on this page:http://www.freeafricanamericans.com/Archer_Avery.htm