The identity of a woman in a Royal Collection painting has been shrouded in mystery for hundreds of years.

North Norfolk News: The painting Portrait of a Woman, which has been identified as Mary Boleyn. Image: Royal Collection TrustThe painting Portrait of a Woman, which has been identified as Mary Boleyn. Image: Royal Collection Trust (Image: Archant)

But now the subject of the artwork Portrait of a Woman has been identified as Anne Boleyn’s lesser-known sister Mary Boleyn.

Thought to have been born at the Boleyn family’s Norfolk seat, Blickling Hall, Mary was the mistress of King Henry VIII before his eye turned to Anne.

The portrait was one of 14 painting’s of beautiful women that once adorned Windsor Castle. Portrait of a Woman was separated from the collection in the 19th century, but has now been reunited with the other works after an investigation revealed it was from the same series painted by Flemish artist Remigius van Leemput.

Researchers from the Jordaens Van Dyck Panel Paintings Project used a technique called dendrochronology to date painting’s wood, allowing them to confirm it was part of the same set.

North Norfolk News: Henry VIII, who took Mary Boleyn as his mistress before marrying her sister, Anne Boleyn. Picture: Artwork by Hans HolbeinHenry VIII, who took Mary Boleyn as his mistress before marrying her sister, Anne Boleyn. Picture: Artwork by Hans Holbein (Image: Archant)

Dr Justin Davies, one of the project’s founders, said the painting had previously been associated with Mary, but the Royal Collection did not consider it to be of her. Dr Davies said: “The..painting has only been known since 1762. It was called Mary Boleyn then and is the common image found online and in history books but without any evidence that it is her.”

Little is known about Mary Boleyn compared with her sister Anne, whose relationship with Henry VIII led to his break with the Catholic world and the foundation of the Church of England.

She was likely educated at Hever Castle in Kent along with Anne and their brother George.

Mary became a maid-of-honour to Catherine of Aragon after a spell at the royal court of France, where she was considered a great beauty.

North Norfolk News: Scarlett Johansson as Mary Boleyn in the 2008 film The Other Boleyn Girl. Image: Universal PicturesScarlett Johansson as Mary Boleyn in the 2008 film The Other Boleyn Girl. Image: Universal Pictures (Image: Archant)

She married twice. Her first husband, courtier William Carey, died of a mysterious disease called the sweating sickness. Henry VIII had been a guest at their wedding, and at some point she became his mistress, although it is unknown how long the affair went on for.

Mary later married a soldier called William Stafford in secret, and was disowned by her family and banished from court when the marriage become public knowledge.

Mary was the central figure in Philippa Gregory’s 2001 novel The Other Boleyn Girl, which was made into a 2008 film, with Scarlett Johansson playing the role.

North Norfolk News: Molly Housego in Tudor attire at a pageant at Blickling Hall, where Anne and Mary Boleyn were throught to have been born. Image: Colin FinchMolly Housego in Tudor attire at a pageant at Blickling Hall, where Anne and Mary Boleyn were throught to have been born. Image: Colin Finch (Image: Archant)

North Norfolk News: Blickling Hall Picture: ANTONY KELLYBlickling Hall Picture: ANTONY KELLY (Image: Archant Norfolk 2018)