Casgliadau Celf Arlein
Pori artistiaid ‘o’
- OLIVER, William (fl.1867 - 1897)
- OLSSON, Julius (1864 - 1942)
- OPIE, John (1761 - 1807)
- ORPEN, William, Sir (1878 - 1931)
- OSBORN, Emily Mary (1834 - >1913)
- OWEN, Isambard (1850 - 1927)
- OWEN, William (1769 - 1825)
- OXLAND, Joan (1920 - )