- O'Riley, Addie1
- O'Riley, Kathleen1
- O'Riley, Mamie1
- Osborne, Henry Kimsey, 1874-19491
- Owens, Frank Capers, 1898-19831
- Owens, Henry Grady, 1892-19851
- Owens, Lawrence Beacham, 1869-19411
- Pacifists1
- Padgett, Brantley George, 1919-19661
- Padgett, Christopher Gadsden, 1916-20021
- Panoramas1
- Parks--South Carolina1
- Payne, John, 1912-19891
- Peace, Charlie, 1903-19581
- Pearson, Gordon Trout, 1910-19821
- Peden, Ralph Henry, 1908-19691
- People displaced by eminent domain1
- Pershing, John J. (John Joseph), 1860-19481
- Photographers1
- Pipe smoking1