Ania Marson is an Anglo-Polish actress. Her roles include playing the Grand Duchess Olga Nikolaevna of Russia in Nicholas and Alexandra (1971), and the demon Voleth Meir, 'the Deathless Mother' in The Witcher

Ania Marson was born May 22, 1949, in Gdynia, Pomorskie Voivodeship, Poland. She studied acting at the Corona Stage Academy

In 1963, Marson appeared on television in the series Dixon of Dock Green, then in other series such as The Troubleshooters in 1968 and Detective in 1969. In the 1970s, she appeared in Puppet on a Chain, and Nicholas and Alexandra in 1971, in which she played the Grand Duchess Olga Nikolaevna of Russia. She subsequently appeared in Emma in 1972, The Abdication (1974), Blake's 7 (1978). and Bad Timing in 1980.

In 2011 she appeared as Diana in Home Death, directed by Fiona Morrell, at the Finborough Theatre. In 2015, after a twenty-five year absence from film and television, she appeared as Olga Kowalski in an episode of Foyle's War.

In 2021, she played the demon Voleth Meir, 'the Deathless Mother' which feeds on misery, pain, and hate, in season two, for five episodes of The Witcher, alongside Anya Chalotra