What event brought the Tudors into power?
[since the submitter didn't include an email address, and this is basic question, I'll just go ahead and answer it in the post]
The Battle of Bosworth Field on August 22, 1485 was the actual *event* that brought Henry VII to the throne.
Off the top of my head, I would suggest Michael Bennett's "The Battle of Bosworth" and "The Making of the Tudor Dynasty" by Griffiths and Thomas if you want to learn more.
Anyone want to add other comments, please chime in!