– 22 December 1959) was the natural daughter of Alexander II of Russia by his mistress (later his wife), Princess Catherine Dolgorukova.

Catherine was born at Saint Petersburg, Russia, on 9 September 1878, while her mother was still the mistress of Tsar Alexander II.

When she was less than two, her parents' morganatic marriage on 6 July 1880 legitimated her, and she acquired the surname of Yurievsky, the title of knyagina (princess) and the style of Svetlost (Serene Highness).

[7] Catherine's brother George died, after a long illness, on 13 September 1913 in Marburg, Hesse, and was buried at St Elizabeth's, Wiesbaden.

In 1932, Catherine bought a house called "The Haven" on Hayling Island, Hampshire, which she chose for its climate, as she suffered from asthma.

On 29 November 1934, she attended the wedding at Westminster Abbey of her grand-niece Princess Marina of Greece and Denmark to Prince George, Duke of Kent.

He noted in his diary that she was living in "a ghastly villa called the Haven in Sinah Lane; there is the sea not far away, peace, poverty, and a Pekinese!

Only two members of the family attended her funeral, her former husband Serge Obolensky and her nephew, Prince Alexander Yurievsky (1901–1988), the son of her brother George.