Mary, unlike Anne, was the mistress of two kings - François I of France and England's Henry VIII. She was born sometime between 1499 and 1508, probably around 1500. She was considered the more attractive of the two, and was the one member of the Boleyn family who ultimately was able to avoid the controversies that led to the executions of both her sister Anne and her brother George.
She was married twice, and died in 1543. Philippa Gregory was intrigued by the story of a queen's sister who apparently has been forgotten by history, but seemed to have been the more interesting of the two sisters. Some of the novel's storyline was loosely based on the work of American historian, Retha M. Warnicke, and the books of British historian, Alison Weir. Others, however, were clear dramatic devices. As a novelist, Gregory also often altered or ignored actual historic events to portray Mary Boleyn in a more positive light, particularly through her portrayal of Mary as a heroine, determined to achieve independence unheard of for an upper-class woman in the mid-sixteenth century.