The Red Queen by Philippa Gregory

Heiress to the red rose of Lancaster, Margaret Beaufort never surrenders her belief that her house is the tru ruler of England. Igorded by her sainted cousin Henry VI, mocked by her mother, married at age twelve, and endangered by childbirth, she sets her heart on putting her son on the throne regardless of the cost to herself, to England and ever to the little boy. She names him Henry, like the king; sends him into exile; and pledges him in marriage to the daughter of her sworn enemy, Elizabeth of York. Margaret charts her won way through loveless marriages, treacherous alliances, and secret plots. Finally, gambling her life that her husband, the ruthless, deceitful Thomas, Lord Stanley, sill support her, she masterminds of the the greatest rebellions of all time - all the while knowing that her son has grown to manhood, recruited an army, and now waits for his opportunity to win the greatest prize.