Mary, Queen of Scots supported the plan to marry the Duke and perhaps take the English throne. The Revolt of the Northern Earls started as a conspiracy to marry her to the Duke of Norfolk, a plot many at court knew of. They hoped that if Mary married the Duke their children would be Protestant, leaving Elizabeth open to naming Mary as her heir, so England would still have a Protestant Monarch. It was unpopular for several reasons: marriage of members of the nobility required the monarch's consent, Elizabeth had made it clear that succession was part of the royal prerogative, and the Duke of Norfolk was sympathetic to Catholics and close to the Earls of Northumberland and Westmorland, who would prefer Mary to be on the throne