I know it has been a couple of years since your last post on this subject, but I am very interested in the Francis Marion Davis you are speaking about. I have been working filling in areas in my families genealogy that my uncles before me have started. Maybe you can help fill in some of the blanks.
I am a 3 great granddaughter to Francis Marion Davis, whose headstone reads as you had stated (Capt 12th Mo Cav). He is buried in Caney Cemetery in Cherokee Co, OK. I have a pic of his headstone and others that were around his during my visit to the cemetery in 2006. Your last name is an interest also, since my 2great grandfather was a Cantrell that married FM Davis' oldest daughter (Sara Elizabeth). I know a few of her siblings married Cantrell's as well.
I just recently began to work on this line trying to dig deeper to find answers. It seems that yes, the more I learn, the more questions I have!! Hugh had it right on that one!
I live in the Northwest Arkansas area so things are a bit easier to research, when time allows that is. Maybe we can compare notes. I'm willing to share what little bit I have with you. Plus it seems I am gaining more information on a daily basis at the moment!!
My email is email@example.com. Feel free to contact me.