From “Henry V – The Scourge of God” by Desmond Seward:

The Siege of Caen, Normandy, 1417

On the morning of 4 September, after hearing three Masses, the king ordered a general assault on the lower part of the town. He was rumoured to have had an encouraging vision of a fiery cross. The first onslaught was beaten back with the help of showers of burning oil, powdered quicklime and scalding water, as well as volleys of crossbow bolts and stones. One young Englishman, Sir Edmund Springhouse, fell into a ditch behind one of the breaches and was burnt alive by the French, who hurled bales of burning straw down on to him, infuriating his comrades. Henry sent in a second and a third wave of men-at-arms, who climbed down into the breaches and then up to engage the enemy hand to hand. The defenders heard an uproar behind them, panicked and gave ground. Clarence had attacked simultaneously from the opposite side of the new town. A man named Harry Ingles clambered over the rubble and led the duke's men-at-arms as they hacked their way in towards the town centre. The royal brothers met in the middle of it, joining forces to mop up what was left of the defence.

If the chronicles are to believed, the victors then herded all the population they could find, civilian as well as military, regardless of sex, into the market place where, on Henry's orders, they massacred at least 2,000 of them. Blood ran in streams along the streets. The king ordered the killing to stop after coming across the body of a headless woman with a baby in her lap still sucking at her breast. Instead he sent his men through the streets, crying 'Havoc!' to loot and rape. (Anything of value, however, had to be surrendered to his officials.) Crowds knelt in the street as Henry passed, begging for mercy.

On 5 September under his signet he wrote the usual amiable letter to the mayor and aldermen of London: 'God of his high grace sent unto our hands our town of Caen, by assault and with right little death of our people. . . we and our host been in good prosperity and health.' One of the greatest historians of the king, Waugh, has written: 'It is humiliating to our pride in a national hero to read the language of those who suffered under his heavy hand, for when the broken spirit of the French began to revive, the foul massacre of Caen was ever foremost in their minds.' (This may be an honest enough admission on Waugh's part but is also a good example of the bias in Henry's favour which still afflicts English historians.)

The old town and the citadel surrendered sixteen days later. The citadel could probably have held out for many months, but its garrison's spirit had been broken by the almost contemptuous ease with which Henry had smashed his way through the new town's supposedly impregnable walls. They can have had little faith in the ability of a relieving force to overcome so terrible an opponent. Moreover, with shrewdly calculated moderation, he offered surprisingly generous terms. The men were allowed to march off with their arms and keep up to 2,000 gold crowns, the women to retain their jewellery.

The fall of Caen, together with the butchery of its citizens, was widely reported. In Venice, Antonio Morosini received letters 'from divers parts' informing him that the king had 'ordered his subjectsbarons and knights, and all his men-at-arms - to kill and cut to pieces everyone they found, from the age of twelve upwards, without sparing anybody. . . no one had ever heard of such infamy [nequicia] being committed'. More importantly, as he must have intended, Henry had struck fear into all Normandy. The Monk of St Denis reports that 'by taking the town of Caen, the King of England had inspired such terror in the Normans that they had lost all courage'. Furthermore, he now had a base from which to conquer Lower Normandy where he could be swiftly reinforced from England, since his ships were able to sail straight up the Orne to Caen. Its marble quarries provided him with good gunstones. As at Harfleur, his behaviour was that of a conqueror who intended to stay for good. The citadel - a large square white donjon with four towers at the angles, very like the Tower of London - became one of his favourite personal residences. In his usual pious way he at once installed a lavishly furnished chapel royal in it. He also confiscated many of the best houses in the city, earmarking them for English settlers. Not less than 500 burgesses - perhaps as many as 2,000 - left rather than stay under English rule.