This film, and the book it's based on, were clearly not made with historical accuracy in mind.
- Mary's personality was supposedly more like Anne's is depicted in the movie, so Anne may have been more delicate rather than the other way around.
- Anne's relationship to Henry Percy was well-known, and Henry's first taking notice of her was preventing the marriage. While we will never know for certain their relationship, Percy's objection that he could not "conscionably" end his engagement to Anne could be simply referring to having made a solemn oath rather than referring to the relationship being consummated.
- Anne correctly blamed Cardinal Wolsey and Henry for ending her relationship with Henry Percy rather than Mary who had nothing to do with it ending.
- Mary was banished from the English Court by the Boleyn family for marrying below her station, not because she was a threat for Henry's affection.
- When Mary's first husband died she was left destitute until Anne stepped in and forced the Careys to honour the terms of her marriage contract. Then she was kicked out of court because she married William Stafford, a soldier. The sisters never spoke again. Mary and Stafford were banished to remain in Rochford Hall. The rest of the Boleyns died within three years of each other after the execution of Anne and so Mary inherited what she was allowed by the state (admittedly, not much) shortly before her own death four years after her father. Her children, Catherine Carey and Baron Hunsdon, were good friends with Queen Elizabeth, though.
- Mary was between one and seven years older than Anne.
- The back-and-forth marriage arrangements with William Carey are entirely fictional; Carey was probably chosen for Mary because he was the best the Boleyns could get given Mary's status as "damaged goods". Anne was at the time intended for her cousin James Butler, the future Earl of Ormond.
- The details of Mary's actual affair with Henry are completely and totally unknown; we only know it happened because Henry mentioned it in a petition he sent to the Pope before he broke with Rome. It might have been as short as a single encounter, and may have occurred as early as 1518.
- There is zero evidence that either of Mary's children were Henry's, and in fact it's extremely unlikely they were as Henry was known to never sleep with married women.
- That being said, some historians do suspect of the two, Mary's daughter Catherine Carey was the most likely to be fathered by Henry. For whatever it's worth, Elizabeth was very close to Catherine & Henry Carey, with Catherine being a lady-in-waiting for the Queen.
- Henry did not want his ministers to "look for an excuse" to be separated from Catherine of Aragon. He had always known of the Papal Dispensation granted to permit Henry to marry Catherine (as she had been married first to Henry's older brother Arthur) and always had doubts it was right for the Pope to do such. As Catherine fertility years had passed and Henry had no male heir he looked to Scripture to "explain" why he had no son from Catherine when his mistress Bessie Blount had given him a son. He would have left Catherine regardless of Anne.
- The real Anne and Henry seem to have married twice; once without witnesses in November 1532, once privately but with witnesses in January 1533. (Marriage at the time could be contracted without witnesses.)
- There is of course no evidence that Henry raped Anne.
- Henry VIII never for a moment considered marrying Mary Boleyn in any way, shape, or form whatsoever at any time.
- While Henry VIII did have an illegitimate son (Henry FitzRoy, literally 'Henry, the King's son') between the births of Mary and Elizabeth, his mother was Elizabeth "Bessie" Blount, not Mary Boleyn.
- Mary Boleyn did not take in and raise the future Queen Elizabeth as the movie suggests; in fact, they never met after Mary was banished.
- Anne Boleyn did not take Henry Carey away from Mary either. She made him her ward, which was mainly a financial transaction meant to protect his inheritance.
- Anne was accused of having adultery with five men, including George (whereas the film suggests it was just George). The accusations are thought to have been cooked up by Thomas Cromwell out of nothing, probably at Henry's instigation.
- Jane Parker didn't give testimony in court and in fact there's no evidence she was involved with the trial in any way. (The testimony often attributed to her seems to have come from another lady interrogated by Cromwell.)
- Anne's stay in France was not a punishment, but a tremendous honour, and she was in her mid to late teens at the time — she spent her formative years there and always had fond memories of her time with the French court.
- Anne Boleyn walked to her execution with her head held high and a supremely calm demeanour. Here, she's shown whimpering and struggling not to cry as the executioner raises his sword.
- Thomas Boleyn was completely against having his daughter sleep with, much less marry, the king. When Henry began harassing Anne, Thomas sent her back to the family's estate in the hopes that Henry's attraction to her would cool off, risking his prestige (and possibly his life) in the process.
- Henry VIII never named a warship after Mary Boleyn. The Mary Rose, a real Tudor Navy ship and the likely inspiration for this scene, was launched when Mary herself was all of 12 years old (in 1511) and was named after either Henry's favourite sister Princess Mary or, much more likely, the Virgin Mary (see here
for more).
