Ultimately the Princess of Battenberg was an eccentric character who turned her back on royal life in favour of philanthropy and religion after suffering numerous hardships – from being separated from her children to undergoing controversial treatment at the hands of psychologist Sigmund Freud.

She is briefly portrayed in The Crown’s third season, but the show hardly scratches the surface of her story. So who do we know about this fascinating figure?

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An English princess who married Greek royalty

Princess Alice was born in Windsor Castle in 1885 to Prince Louis of Battenberg and Princess Victoria of Hesse, granddaughter of Queen Victoria, making her British royalty by blood. Alice was born deaf and by the age of eight, she could lip read three languages, The Washington Post reports.

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Years of exile

Alice showed her devotion to helping the needy early on, when she worked in field hospitals during the Balkan wars of the early 1910s. “God, what things we saw,” she wrote in a letter to her mother, according to The Washington Post. “Shattered arms, legs and heads – such awful sights. Cast off bandages knee-high, the corridor full of blood.”

Sanatoriums and Sigmund Freud

However by 1930 Alice was diagnosed with schizophrenia and sectioned by her family. She apparently had delusions that she was flirting with Jesus Christ and would use sexual language to describe the relationship, according to a documentary by Real Royalty.

Freud believed that her erotic history had been repressed. A CNN report said that she pled her sanity, but was held there for over two years in total.

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Her children’s links to Nazis

According to The Washington Post, the princess was finally reunited with her children in 1937 when she attended the funeral of her daughter Cecilie who had been killed in a plane crash while pregnant. It was at this funeral that Prince Philip was photographed marching alongside men in Nazi uniforms.

The reason? Alice’s daughters had all married men who were members of the German aristocracy and three of those men became Nazis, per Town & Country magazine.

Nevertheless, not long after this Prince Philip became an officer in the British Royal Navy, which would eventually pit him against his in-laws.

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Holocaust hero

During World War II, Alice moved back to Greece to help the needy. According to The Guardian, she sheltered a Jewish family from the Nazis in her flat in Athens.

The Washington Post details how she was interviewed by the Gestapo several times when the Germans became suspicious, but used her deafness to pretend she could not communicate effectively with them. She was later honoured by the Yad Vashem Holocaust Museum in Jerusalem and even requested her grave be buried at the foot of the Mount of Olives in Israel, per Real Royalty.

Rejecting royal life to be a nun

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But it was at Elizabeth’s coronation that Prince Philip’s mother turned heads, walking alone down the aisle dressed in a nun’s habit.

The Princess of Battenberg established an order of nuns in 1949 called the Christian Sisterhood of Martha and Mary. She spent her final years as a chain-smoking sister, raising funds and even selling her royal jewellery for the cause, according to Elle.