"It was as if somebody was trying to hide something."
Actually, it's nothing of the kind.
http://genforum.genealogy.com/me/messages/18714.html
http://freepages.genealogy.rootsweb.com/~nnnotables/zwgh.html
http://www3.dcs.hull.ac.uk/cgi-bin/gedlkup/n=presidents?presidents2095
http://www.burkes-peerage.net/sites/contents/book/america/fhp/apf/fhp-APF-HARDING-29-BIO.asp
Thank you for replying. I found your lists of some of Hardings ancestors to be interesting. I am recalling from memory the exact words of the author (the book is in storage and buried in a box.) Some of Harding's family relations appeared to be murky. I think there as a case of not to much known about them or there ethnicity was not established and it was in a way that was very mysterious to the author who was a leading scholar of American First Ladies. Any black ancestry I think was not from the Mayflower obviously. But it was apparent that Harding was considered black by many people in Marion including his own Step father who actually campaigned against him on that ground. The step father later accepted the marriage and was quoted as saying that Harding was the "smartest nigger I have ever known" (his language not mine). I don't know actually what the truth is about Harding's lineage but I suspect his own stepfather would have known the truth.