[It's me]

MAry "siezed" the reigns of power because she was the rightful heir. Even Elizabeth I knew that.

[lavrenti]

Mary was a Catholic, and had no business sitting on the throne. She basically changed the rules after getting the Privy Council to back her.

Rightful heir has a nice ring to it, but it was intended that no Catholic sit on an English throne. Mary had as much right to be queen as a washerwoman.