-O-
- Oakeley of Oakley; Commoners of Great Britain and Ireland
- Oakley; Commoners of Great Britain and Ireland
- Oates; American Families with British Ancestry
- Oates, Brawley (History of Mecklenburg Co. Nc)
- O' Brien of Bird Hill; American Families with British Ancestry
- O' Brien of Nenagh; American Families with British Ancestry
- O'Brien, Rev. James
- O'Connor, Eugene
- O'Connor, Patrick Joseph
- O' Conor; American Families with British Ancestry
- Ogden of NY; American Families with British Ancestry
- Odom, Jacob, Morgan Co., GA Deed
- Ogilby; American Families with British Ancestry
- Oglesby, D. P. of Elbert Co., GA
- Oglethorpe, James Edward, General by Jeannette Holland Austin
- O'Hara of Norfolk, VA; American Families with British Ancestry
- Olcott of CT; American Families with British Ancestry
- Older of London; American Families with British Ancestry
- Olds; American Families with British
- Olds of England, CT, VT, NY & Elbert Co;s GA
Olive of Oglethorpe Co., GA
- Oliver of Elbert Co., GA
- Olivier, Ray
Ancestry
- Oliver of NJ; American Families with British Ancestry
- Orcutt; American Families with British Ancestry
- Orme of Pennsylvania, Maryland & Georgia
- Orr of Hall Co., GA
- Osborne of Transylvania Co., NC
- Osborne, James W., sketch (History of Mecklenburg Co. Nc)
- Osborne, James W. (History of Mecklenburg Co. Nc)
- Osgood of MA; American Families with British Ancestry
- Osgood of Liberty Co., GA
- Oswalt of Lexington Co., SC
