Between 1270-74 England was engulfed by a rising tide of lawlessness. This was triggered by Lord Edward's absence on crusade, the lingering resentments of the Montfortian wars, and the incapacity of central government. 

One of those entrusted with guarding the kingdom was Edward's uncle Richard, Earl of Cornwall. Richard was competent and immensely rich, able to bring the authority of his royal status, wealth and prestige. In October 1270, for instance, he appointed a new sheriff of Lincolnshire and granted the castle and county of Carlisle to the bishop of that diocese. A few months later, March 1271, Richard took charge of suppressing a mysterious rebellion in Yorkshire; he gave orders for the arrest of 'all persons making congregations, conventicles and conspiracies against the peace' in that county. This was just one of the 'wars and rumours of wars' that were erupting all over England. 

Then, a piece of appalling news reached London. Richard's son, Henry of Almaine, had been murdered at the church of Viterbo in Italy. While attending Mass at the Chiesa di San Silvestro, he was attacked by Simon de Montfort junior and his brother Guy. When Henry clung to the altar, begging for mercy, they cut his fingers off and dragged him outside. There, in full public view, they cut out his eyes and testicles and finally hacked off his head. 

This, Simon declared, was in revenge for the bloody death of his father at Evesham in 1265. Since Henry was not even present at Evesham, let alone culpable, Simon's defence was preposterous. In any case, blasphemy and homicide were just that, regardless of motive. 

The murder had a destabilising effect on England, as it was supposed to. Richard never recovered from his son's death: in December 1271 he suffered a near-fatal stroke that left him paralysed down one side and unable to speak. After lingering for a few months, he died at Berkhampstead on 2 April 1272. Meanwhile England slid further into chaos.