| Name | Functions | Event Dates  | Events | Resources | ||
|---|---|---|---|---|---|---|
| Nicholas Orloff | Actor | 1908 | 1 | 1 | ||
| William Owen | Actor | 1908 | 1 | 1 | ||
| Bronisław Oranowski | Actor, Translator | 1907 - 1911 | 3 | |||
| E A Ozerova | Actor | 1907 | 1 | |||
| Augusta Olsen | Actor | 1907 | 10 | |||
| Georg Ottmay | Actor | 1906 - 1961 | 8 | |||
| Teresina Oster | Actor | 1906 - 1909 | 4 | |||
| Marg. Otto | Actor | 1906 - 1908 | 3 | |||
| Pál Olasz | Actor | 1906 - 1908 | 4 | |||
| Warner Oland | Actor | 1906 - 1908 | 5 | 1 | ||
| Clara Osmond | Actor | 1906 - 1907 | 3 | |||
| Ottilie Olsen | Actor | 1906 | 1 | |||
| Edyth Olive | Actor | 1906 | 1 | 1 | ||
| Walter Orchowski | Actor | 1906 | 1 | |||
| Ole Onsøjen | Musical Director | 1906 | 1 | |||
| - Oberhofer | Actor | 1906 | 1 | |||
| Herbert O'Connor | Actor | 1906 | 1 | |||
| Ida Orloff | Actor | 1905 - 1942 | 26 | |||
| Sava Ognjanov | Actor, Director | 1905 - 1928 | 8 | |||
| (Nuna) Młodziejowska Olchowska | Actor | 1905 - 1907 | 2 | |||
| Piero Ottolini | Translator | 1905 - 1906 | 4 | 1 | ||
| Edith Otis | Actor | 1905 | 1 | |||
| James O'Shea | Actor | 1905 | 1 | |||
| Ferdinand Onno | Actor | 1904 - 1938 | 9 | |||
| Stanisław Orlik | Actor | 1904 - 1924 | 4 | |||
| Janusz Orliński | Actor | 1904 - 1916 | 9 | |||
| Anna Oehlschläger | Actor | 1904 - 1908 | 2 | |||
| Hans Oberländer | Director | 1904 - 1908 | 2 | |||
| Helen Ormbee | Actor | 1904 | 1 | |||
| Jane Oaker | Actor | 1904 | 1 | 1 | ||
| Kathleen O'Neill | Actor | 1904 | 1 | |||
| Władysława Ordonówna | Actor | 1904 | 1 | |||
| Pavel Orlenev | Actor, Director | 1903 - 1923 | 14 | 1 | ||
| Janusz Orliński | Actor | 1903 - 1909 | 4 | |||
| Marta Ozoliņa | Actor | 1903 | 1 | |||
| Elita Proctor Otis | Actor | 1903 | 13 | |||
| Rasmus Ottesen | Actor | 1902 - 1926 | 18 | |||
| Thomas Oikonomou | Actor, Director | 1902 - 1926 | 121 | |||
| Castora Ohlsen | Actor | 1902 - 1909 | 3 | |||
| Federico Oliver | Director | 1902 - 1908 | 5 | |||
| Hans Olsen | Actor | 1902 - 1903 | 17 | |||
| Hertha Olden | Actor | 1902 | 2 | |||