Henry Tudor, the future Henry VII, has been called the most unlikely King of England. Yet his rise from obscurity was foretold by the bards, and by 1485, the familial bloodbath of the Wars of the Roses left Henry as the sole adult Lancastrian claimant to the throne. The hunchback usurper Richard III desperately wanted him dead, and in his exile Henry Tudor was left with no choice. He either invaded England or faced being traded to Richard to meet...