Princes in the Tower act stated that Edward IV and Elizabeth Woodville's marriage was invalid because of Edward's pre-contract of marriage with Lady Eleanor Butler. Gloucester was crowned King Richard III of England on 3 July. The declaration of the boys' illegitimacy has been described by Rosemary Horrox as an ex post facto justification for Richard's accession. Dominic Mancini, an Italian friar who visited England in the 1480s and who was in London in the spring and summer of 1483, recorded that after Richard III seized the throne, Edward and his younger brother Richard were taken into the "inner apartments of the Tower" and
Princes in the Tower or heavily influenced by John Morton, Archbishop of Canterbury, in order to incriminate Richard III. Robert Fabyan's "Chronicles of London", compiled around 30 years after the princes' disappearance, names Richard as murderer. Thomas More (a Tudor loyalist who had grown up in the household of John Morton, an avowed foe of Richard III), wrote The "History of King Richard III", c.1513. This identified Sir James Tyrrell as the murderer, acting on Richard's orders. Tyrrell was the loyal servant of Richard III who is said to have confessed to the murder of the princes before his execution for treason in 1502.