Young Bess (1953)

Maybe not quite how it actually happened, but this was Hollywood, remember. Jean Simmons plays the Princess Elizabeth brought up in rags and riches depending on the whim of her father Henry VIII (rather rumbustiously played by Charles Laughton). Meantime Thomas Seymour (a handsome, swashbuckling rogue played by Stewart Granger) is marrying Henry's widow Catherine Parr (Deborah Kerr) and so we have our menage-a-trois. History is fact about the marriage; much less so about the "love affair" between Elizabeth and Seymour. This film follows her coming-of-age as she navigates the political intrigues after her father's death. It's is colourful and engaging - her two servants add quite a lot too. It's entertainment though, nothing too educational.