| # |
Last Name, Given Name(s)  |
Person ID |
Born/Christened  |
Location |
| 1901 |
 Count of Blois Odo I | I2992 | b. 950 | |
| 1902 |
Count of Blois Odo II | I2991 | b. 990 | |
| 1903 |
King of Scots Oengud Macfergus | I3772 | | |
| 1904 |
King of Ulster Oengus Finn | I9371 | b. Abt 215 | Ulster, , Ireland  |
| 1905 |
Oengus mac Maelcobo | I9342 | b. Abt 640 | Ulster, , Ireland |
| 1906 |
King of Angles Offa | I2117 | b. 345 | |
| 1907 |
Ogive of Luxembourg | I2133 | | |
| 1908 |
Ogne Norbrilsdottir of Northumbria | I5044 | b. 530 | |
| 1909 |
Ogyek of Hungary | I4118 | b. 796 | Dentumogeria, Central Asia |
| 1910 |
King of Sweden Ohthere | I8619 | | |
| 1911 |
King of Ireland Oilioll Finn | I4428 | b. 860 BC | |
| 1912 |
Oiriu ingen Fergus | I9384 | b. Abt 665 | Ulster, , Ireland |
| 1913 |
King of The danes Olaf | I5034 | b. 391 | , , , Denmark |
| 1914 |
King of Sweden Olaf | I1978 | b. 885 | |
| 1915 |
King of Sweden Olaf Bjornsson | I3072 | | |
| 1916 |
King of Dublin Olaf Cuaran Sitricsson III | I2887 | b. 921 | |
| 1917 |
King of Dublin Olaf Sihtricson II | I2885 | b. 1000 | |
| 1918 |
Regent of Kiev Olga | I2485 | b. 890 | |
| 1919 |
Olioll | I16133 | | |
| 1920 |
King of Ireland Olioll Cas-fiachlach | I4270 | b. 490 BC | |
| 1921 |
Olioll mac Nathi | I9516 | b. Abt 475 | Ard Ladrand, Leinster, Ireland |
| 1922 |
Count of Carcasonne Oliva I | I4901 | b. 800 | |
| 1923 |
Count of Carcasonne Olvia II | I4900 | b. 830 | |
| 1924 |
Oncea | I2755 | | |
| 1925 |
Oneca of Pamploma | I2751 | | |
| 1926 |
King of Sweden Ongentheow | I8924 | | |
| 1927 |
Ophir | I9961 | | |
| 1928 |
King of Asturias Ordono I | I2303 | | |
| 1929 |
King of Leon Ordono II | I2301 | b. 873 | |
| 1930 |
King of Leon Ordono III | I2299 | b. 926 | |
| 1931 |
Orengaede, Wife of Lusignan | I2384 | | |
| 1932 |
Queen Consort of Wessex Osburga | I1089 | | |
| 1933 |
Grand Butler of England of Hampshire Oslac | I1090 | | |
| 1934 |
Osnad ingen Ciantestach | I9316 | b. Abt 880 | , , , Ireland |
| 1935 |
Ostrida Regenwaldsdatter | I3521 | b. 990 | Gothland, Sweden |
| 1936 |
King of The goths Ostrogotha | I5069 | b. 171 | |
| 1937 |
Count of Vermandois Otho Otto | I2498 | b. 979 | |
| 1938 |
Duke of Carinthia Otto | I2997 | | |
| 1939 |
Duke of Swabia Otto II | I3150 | | |
| 1940 |
Duke of Saxony Otto | I2166 | b. 836 | |
| 1941 |
King of Germany Otto I | I2179 | b. 23 Nov 912 | |
| 1942 |
Emperor of the Holy Roman Empire Otto II | I2843 | b. 955 | Saxony, Germany |
| 1943 |
Ouicant Ap Outigern of Britain | I4662 | b. 180 | |
| 1944 |
Oumun Ap Dyfwn of Gwenydd | I4641 | b. 160 | |
| 1945 |
Outigern Ap Eliud of Britain | I4663 | b. 160 | |
| 1946 |
Owain Ap Cyllin of Dumnonia | I4675 | b. 0090 | |
| 1947 |
Lord of Tegaingl Owain Ap Edwin | I2905 | b. 1044 | Llys Edwin, Llaneurguin, Flintshire, Wales, United Kingdom |
| 1948 |
Duke of Cornwall Owain Finddu | I4973 | b. 365 | |
| 1949 |
Pacy | I4131 | | |
| 1950 |
Pam | I50 | | |
