Despite having lived in exile since childhood, Henry Tudor had nursed his fragile claim to the English throne. He was content to wait for the right moment which finally came when his cousin, Richard III was killed in the battle of Bosworth Field. Henry quickly announced his betrothal to Elizabeth of York, Richard's eldest daughter, effectively asserting his claim to the throne. Any doubts that the people had about their new king were overcome by their devotion to his wife.
A true marriage of convenience, it was agreed that in exchange for her popularity Elizabeth would rule jointly with her husband. But Henry had no intention of honouring his promise and in doing so soon found that he had made some powerful enemies, people who believed that Elizabeth was the rightful heir and who weren't afraid to act on their beliefs.