'She was very, very unhappy': The Crown actress reveals how Princess Margaret still felt bitter 20 YEARS after the Queen banned her from marrying her divorced lover

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The Crown actress Vanessa Kirby has revealed how she uncovered a startling truth about the late Princess Margaret's relationship with the Queen while researching her role for the Netflix drama. 

In the first episodes, viewers witness Margaret's affair with married Captain Peter Townsend who later divorced his wife to pave the way for marriage to the royal.

But the Queen refused to endorse the match and now Vanessa has reveals how she discovered that Margaret was still bitter about it 20 years later.

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Actress Vanessa Kirby who plays Princess Margaret in The Crown, the Netflix royal biopic, says that Princess Margaret never forgave the Queen for blocking her marriage to divorced Peter Townsend 

While filming, she met someone whose parents had been in the royal's circle of friends. 

The couple had married back in the '70s - two decades on from Margaret's love affair with Townsend - and one of them was a divorcee. 

'He said that Margaret was very, very unhappy about it and made that known publicly,' she explained. 

'I thought: "God 20 years on if you're still resentful towards people who are able to do something you weren't it must mean that you haven't forgiven everybody. Or yourself".'  

rincess Margaret With Group Captain Peter Townsend At Shashi Railway Station Bechuanaland During The Royal Visit To South Africa In 1947

Princess Margaret went on to marry Lord Snowdon, formerly Anthony Armstrong-Jones, after her former lover announced his engagement to a 19-year-old Belgian woman 

She added that while being forbidden to marry someone by your parents is one thing, being prevented by a sister must have been very difficult to cope with. '

It was recently revealed that Princess Margaret hastily announced her engagement to man-about-town photographer Tony Armstrong-Jones after receiving a letter from Townsend to say he was marrying a 19-year-old Belgian woman. 

Four years had passed since Townsend, 16 years her senior and father of two sons from a dissolved marriage, had helped her write the emotional statement in which she announced that, 'mindful of the Church's teaching', she would not marry him. 

However, many felt the truth was that she was not prepared to risk losing her place in the order of accession to the throne.

Vanessa Kirby as Princess Margaret in The Crown. The actress has revealed how the royal was seemingly feeling bitter over not being allowed to marry Captain Townsend two decades later

Princess Margaret at an official royal engagement in 1966 with her husband Lord Snowdon 

Now, in his letter, Townsend told her that he was about to announce his engagement to a Belgian woman, Marie-Luce Jamagne.

His news really upset the princess because it broke a secret pact that neither would marry anyone else. 

They had made it after ending their famous love affair which, for the princess, had begun when she was 14 and the tall, charming air ace arrived at Buckingham Palace as her father George VI's equerry.

The princess had passed her 29th birthday when she read her former lover's shocking letter, several years beyond the age at which most women got married in those days. Townsend was 45. His fiancee, Marie-Luce, who had similar darkly pretty looks to the princess herself, was just 19. 

Sisterly bond: Vanessa Kirby (right) as Princess Margaret and Claire Foy as a young Queen Elizabeth in The Crown 

The Crown sees Wolf Hall star Claire Foy taking on the part of a youthful Queen Elizabeth during the early decades of her marriage to Prince Philip.

Dr Who actor Matt Smith plays the Duke of Edinburgh in Peter Morgan’s much hyped new series The Crown, which documents the couple's relationship from November 1947 to the Suez Crisis of 1956.

Writer Morgan, of course, earned plaudits for The Queen, starring Helen Mirren, and this time teams up with The Audience’s Stephen Daldry for what has been described as a ‘meticulously researched’ and sumptuous series. 

The ten-part drama doesn’t shy away from the grim realities of life, however: including showing a scene in which the Queen’s late father, King George VI, coughs up blood into his toilet bowl.

He died from lung cancer in 1952, propelling his eldest daughter, Princess Elizabeth, onto the throne in her twenties.

The series also shows one of his daughter’s (it is not yet clear which) seeing his body embalmed, which might cause some upset among viewers.

Scenes were filmed both at Elstree Studios and at some of the magnificent stately homes in the country: Hatfield House, Lancaster House, Loseley Park, Wrotham Park and Englefield.

The beautiful period costumes are the handiwork of Michele Clapton, who also designs the costumes for Game of Thrones.