| Birth Place: | Venice, Italy |
| Death Place: | Venice |
| Father: | Danilo I, Prince of Montenegro |
| Mother: | Darinka, Princess of Montenegro |
Olga Petrović-Njegoš (Cetinje, 19 March 1859 — Venice, 21 September 1896), was a Montenegrin princess and a member of the House of Petrović-Njegoš, ruling family of the small Adriatic Principality of Montenegro.
She was born on March 19, 1859, in Venice. She was the daughter and the only child of Danilo I, Prince of Montenegro and his wife, Darinka, Princess of Montenegro.
In 1860, her father died, and was succeeded by Nicholas I.[1] In 1867, she left Montenegro with her mother and settled in Venice.
Princess Olga was described as quite pretty, and as a timid and sweet tempered personality. In accordance with the will of her father, Olga was placed under the guardianship of her mother until she reached the age of eighteen, and after that she was to come in to the inheritance and lands of her father. However, Nicholas I did not give permission to her or her mother to return to Montenegro again once they had left, so she was never able to take control of her inheritance. Reportedly, she had no recollection of Montenegro. Having no real property but still of royal birth, she remained unmarried, since she was expected to marry a royal but her lack of dynastic importance or property never made her a valuable on the royal marriage market. She excelled in languages, spoke them perfectly, but with the same foreign accent. After the death of her mother, she continued living in Venice, surrounded by her maternal cousins, but she frequently visited Russia, sometimes in the company of her paternal cousin, Nicholas I of Montenegro.
With the Russian pension, granted to her by Alexander II, she lived her life in Venice, where she died unmarried and childless. During the last days of her long illness, Prince Tommaso, Duke of Genoa was telegraphed on a daily basis about her health, while Prince Vittorio Emanuele, Count of Turin visited her frequently when he returned from his military maneuvers in Germany.
She died in Venice on 21 September 1896. Her coffin was transferred first from Venice to Cattaro and then to Montenegro, where her remains were buried next to her mother and father, in the Monastery of Cetinje. Princess Olga's funeral was attended by every member of the Montenegrin royal family and the whole diplomatic corps. Special wreath of fresh flowers was sent from Italy by the Queen Margherita, soon to be mother-in-law of her first cousin, Elena of Montenegro.[2]