Realm Divided, Dan Jones

1215 - the penultimate year of the reign of a king with the worst reputation of any in our history - saw England engulfed by crisis. Weakened by the loss of Normandy, King John faced insurrection by his disgruntled barons. With the assistance of the Archbishop of Canterbury, they drew up a list of their demands. In June, in a quiet Thames-side water-meadow, John attached his regal seal -