William af Malmesbury var munk ved Malmesbury Abbey i det sydvestlige England i første halvdel af 1100-tallet. Der vides ikke meget om hans liv, men han har sandsynligvis tilbragt størstedelen af det i klosteret i Malmesbury, hvor han også fungerede som bibliotekar. Han betragtes som en af Englands største nationalhistorikere.
De følgende uddrag stammer fra Gesta regnum Anglorum (de engelske kongers historie), der fortæller de engelske kongers historie frem til kong Stephens regeringstid i midten af 1100-tallet. I disse afsnit beretter William af Malmesbury om Danemordet i 1002, hvor den angelsaksiske kong Æthelred beordrede alle danere i England myrdet, og de efterfølgende begivenheder. Ifølge ham skyldtes angelsaksernes mange problemer i tiden omkring år 1000 kong Æthelreds dovenskab og hovmod, og der trækkes en lige linje fra Danemordet 1002 til Svend Tveskægs invasion i 1013.
[…] In the midst of these pressing evils, the expedient of buying off hostilities by money was again debated and adopted; for first twenty-four, and soon after, thirty thousand pounds were given to the Danes: with what advantage, succeeding times will show. To me, indeed, deeply reflecting upon the subject, it seems wonderful, how a man [kong Æthelred 2.], as we have been taught to suppose, neither very foolish, nor excessively heartless, should pass his life in the wretched endurance of so many calamities. Should any one ask me the reason of this, I could not easily answer, except by saying, that the revolt of the generals proceeded from the haughtiness of the king. Their perfidy has been spoken of before: I now hasten to instances of his violence, which was so intolerable, that he spared not even his own relations. For, besides the English, whom he despoiled of their hereditary possessions without any cause, or defrauded of their property for supposititious crimes: besides the Danes, whom, from light suspicion only, he ordered to be butchered on the same day throughout England; which was a dreadful spectacle to behold; each one compelled to betray his dearest guests, now become dearer from the tenderest connexions of affinity, and to cut short their embraces with the sword: yet besides all this, I say, he was so inconstant towards his wife, that he scarcely deigned her his bed, and degraded the royal dignity by his intercourse with harlots.
[…] But king Ethelred, after the martyrdom of Elphege, was we have related, gave his see to a bishop named Living. Moreover, Turkill, the Dane, who had been the chief cause of the archbishop’s murder, had settled in England, and held the East Angles in subjection. For the other Danes, exacting from the English a tribute of eight thousand pounds, had distributed themselves, as best suited their conveniences, in the towns , or in the country; and fifteen if their ships, with the crews, had entered into the king’s service. In the meantime Thurkill sent messengers to Sweyn, king of Denmark, inviting him to come to England; telling him that the land was rich and fertile, but the king a driveller; and that, wholly given up to wine and women, his last thoughts were those of war: that in consequence he was hateful towards his own people and contemptible to foreigners: that the commanders were jealous of each other, the people weak, and that they fly the field, the moment onset was sounded.
Sweyn was naturally cruel, nor did he require much persuasion; preparing his ships, therefore, he hastened his voyage. Sandwich was the port he made, principally designed to avenge his sister Gunhilda. This woman, who possessed considerable beauty, had come over to England with her husband Palling, a powerful nobleman, and by embracing Christianity, had made herself a pledge of the Danish peace. In his ill-fated fury, Edric had commanded her, though proclaiming that the shedding of her blood would bring great evil on the whole kingdom, to be beheaded with the other Danes. She bore her death with fortitude; and she neither turned pale at the moment, nor, when dead, and her blood exhausted, did she lose her beauty; her husband was murdered before her face, and her son, a youth of amiable disposition, was transfixed with four spears. Sweyn then proceeding through East Anglia against the Northumbrians, received their submission without resistance: not indeed, that the native ardour of their minds, which brooked no master, had the first to give example of desertion. On their submission all the other people who inhabit England on the north, gave him tribute and hostages. Coming southward, he compelled those of Oxford and Winchester, to obey his commands; the Londoners alone, protecting their lawful sovereign within their walls, shut their gates against him. The Danes, on the other hand, assailing with greater ferocity, nurtured their fortitude with the hope of fame; the townsmen were ready to rush on death for freedom, thinking they ought never to be forgiven, should they desert their king, who had committed his life to their charge. While the conflict was raging fiercely on either side, victory befriended the juster cause; for the citizens made wonderful exertions, every one esteeming it glorious to show his unwearied alacrity to his prince, or even to die for him. Part of the enemy was destroyed, and part drowned in the river Thames, because in their headlong fury, they had not sought a bridge. With his shattered army Sweyn retreated to Bath, were Ethelmer, governor of the western district, with his followers, submitted to him. And, although all England was bending to his dominion, yet not even now would the Londoners have yielded, had not Ethelred withdrawn his presence from among them. For being a man given up to indolence, and, through consciousness of his own misdeeds, supposing none could be faithful to him, and at the same time wishing to escape the difficulties of a battle and a siege, he by his departure left them to their own exertions.