Nice to hear from you.Appreciate the information regarding Fr. Donald Hebert's books as don't read frenchthis will be a big help.Haven't done any local records search in Louisiana yet other than books at the library but did communicate with someone who did and John Barnhill became Jean Bernhille.So, know what you are talking about when it came to the spelling of names in Louisiana.
As you, I too am a transplant from California but now live in Northeast Louisiana.All my Barnhill family is from the south and don't know much about the northern Barnhills other than at one point all the Barnhills lived in North or South Carolina.After that some of the Barnhill families migrated to the northern states and others to the southern states.
Belong to Ancestry so did try and pull up your grandfather Audley Hiram Barnhill's name.Did find a Audley Barnhill b. 1805 in South Carolina with a daughter, Emma Lavina Barnhill Reasoner b. in Illinois.Then there was a Hiram Audley Barnhill listed also and hope this is of some help to you.