Edward VI
1537-1553, son of Henry VIII and Jane Seymour. Due to his father's testament and the rules of primogeniture, Edward became King when his father died in 1547. Although Edward thought that he ruled England, actual power lay with the Privy Council (a rather small group of councellors and advisors) and the Lord Protector. Edward supposedly was "a cold-hearted prig", according to G.R. Elton, who liked to tell his much older sister Mary off for her Catholicism:
"The lady Mary, my sister, came to me to Westminster, where after greetings she was called with my council into a chamber where it was declared how long I had suffered her mass, in hope of her reconciliation, and how now, there being no hope as I saw by her letters, unless I saw some speedy amendment I could not bear it. She answered that her soul was God's and her faith she would not change, nor hide her opinion with dissembled doings. It was said I did not constrain her faith but willed her only as a subject to obey. And that her example might lead to too much inconvenience." (Edward wrote this in his diary in 1551. He was 14, Mary was 35).
Sources: Elton, G.R. England under the Tudors. London: Methuen, 1965.