The whole business of Richard III being a bad guy was all a misunderstanding. This misinformation is corrected in Black Adder.
http://www.imdb.com/title/tt0084988/
Thanks tlb. Parliament passed the Titulus Regius, delegitimizing “the little Princes” and naming Richard III the lawful king (after his brother died). After Henry VII seized power, he demanded all copies of the TR be burned and Richard III labelled illegitimate, then married Richard III’s niece. The act of relegitimizing her also relegitimized the little Princes, which meant the elder was the rightful king — so, he had them both murdered and disposed of quietly. It is no wonder his descendants were such bloodthirsty killers, given that he was.