The rebellion of the barons was the most serious constitutional crisis of the era, resulting in a takeover of London that forced the King to flee to Windsor. In 1215, he finally agreed to the constitutional demands of the barons, and signed a "Great Charter" (Magna Carta) that curbed the autocratic powers of the monarch.

John had no intention of abiding by the provisions of the charter. His defiance provoked an all-out war, during the course of which he died of dysentery while on the run. A contemporary chronicler remarked that "Hell is too good for a horrible person like him". Now you know why there has never been a King John II.