“ TYRRELL, SIR JAMES (d. 1502) , the supposed murderer of the English king Edward V., and of his brother Richard, duke of York, was a son of William Tyrrell and a grandson of Sir John Tyrrell (d. c. 1437) , who was treasurer of the royal household and was on three occasions Speaker of the House of Commons. The family is said to descend from Walter Tirel, the murderer of William Rufus. During the Wars of the Roses James Tyrrell fought for the Yorkists ”