(1537-53) the king of England from 1547 to 1553. He was the son of King Henry VIII and his third wife Jane Seymour, and the half-brother (= brother by a different mother) of Mary I and Elizabeth I. He became king at the age of ten, so other people, called regents governed on his behalf. One of them persuaded him to change his will, giving the throne to Lady Jane Grey, but the plan failed and Mary became queen when Edward died. During this period, with Edward's support, England became much more strongly Protestant, so that Mary was unable to change it back to Catholicism.