Charter of King Æthelred for St. Fridewide's minster (7. Dec. 1004)

For it is fully agreed that to all dwelling in this country it will be well known that, since a decree (decretum) was sent out by me with the counsel of my leading men and magnates, to the effect that all the Danes who had sprung up in this island, sprouting like cockle amongst the wheat, were to be destroyed by a most just extermination, and this decree was to be put into effect even as far as death, those Danes who dwelt in the afore-mentioned town [Oxford], striving to escape death, entered this sanctuary of Christ, having broken by force the doors and bolts, and resolved to make a refuge and defence for themselves therein against the people of the town and the suburbs; but when all the people in pursuit strove, forced by necessity, to drive them out, and could not, they set fire to the planks and bumt, as it seerns, this church with its omaments and its books.

Anglo-Saxon Chronicle

[1002] This year the king and his council agreed that tribute should be given to the fleet, and peace made with them, with the provision that they should desist from their mischief. Then sent the king to the fleet Alderman Leofsy, who at the king's word and his council made peace with them, on condition that they received food and tribute; which they accepted, and a tribute was paid of 24,000 pounds. In the meantime Alderman Leofsy slew Eafy, high-steward of the king; and the king banished him from the land. Then, in the same Lent, came the Lady Elfgive Emma, Richard's daughter, to this land. And in the same summer died Archbishop Eadulf; and also, in the same year the king gave an order to slay all the Danes that were in England. This was accordingly done on the mass-day of St. Brice; because it was told the king, that they would beshrew him of his life, and afterwards all his council, and then have his kingdom without any resistance.

Guillaume de Jumièges: Gesta Normannorum Ducum (1050's with additions after 1066)

But while, as we learnt above, under such a famous ruler the prosperity of Normandy grew, Æthelred, king of the English, defiled a kingdom that had long flourished under the great glory of most powerful kings with such a dreadful crime that in his own reign even the heathens judged it as a detestable, shocking deed. For in a single day he had murdered, in a sudden fury and without charging them with any crime, the Danes who lived peacefully and quite harmoniously throughout the kingdom and who did not at all fear for their lives. He ordered women to be buried up to the waists and the nipples to be torn from their breasts by ferocious mastiffs set upon them. He also gave orders to crush little children against door-posts. When thus on the appointed day this outburst of violence, death and murder accumulated beyond measure, some quick and active young men took hold of a ship and fled, speedily rowing down the Thames out into the open sea. They crossed the wide sea and finally reached the harbour they sought in Denmark, and they they reported the bloody fate of their people to King Svein. Thereupon the king, deeply moved by great sorrow, summoned the magnates of the realm, and told them what had happened. Carefully he asked their advice as to how he should act. They were all much distressed and bewailed the calamity of their friends and kinsmen and with one voice decreed that every effort should be made to seek vengeance for their blood.

Florence (John) of Worchester: Chronicon ex Chronicis (early 12th century)

[1002] In that same year too, King Æthelred ordered all Danish settlers, greater and less, and of either sex, to be killed because they tried to deprive him and his leading men of life and rule, and to subdue the whole kingdom to their sway.

William of Malmesbury: Gesta rerum Anglorum (early 12th century)

... the Danes, all of whom in the whole of England he had ordered, on the strength of flimsy suspicions to be murdered on the same day (and a pitiful sight it was when every man was compelled to betray his beloved guest-friends, whom he had made even more dear by close ties of relationship, and to disrupt these embraces by the sword) ...

[on Svein Forkbeards invasion of England in 1013] Swein was a man of blood, and needed little persuasion; so he fitted out his ships and came hastening over. The port where he landed is called Sandwich, and his chief purpose was to avenge his sister Gunnhild. Gunnhild, who was a woman of some beauty and much character, had come to England with her husband the powerful jarl Pallig, adopted Christianity, and offered herself as a hostage for peace with the Danes. Eadric in his disastrous fury had ordered her to be beheaded with the other Danes, though she declared plainly that the shedding of her blood would cost all England dear. And for her part, she faced death with presence of mind; she never grew pale at the prospect, nor did she change expression after death, even when her body was drained of blood, though her husband had been killed before her eyes, and her son, a very likely child, pierced by four lances.

[on the murder of 'two very highborn Danes', Sigeferth and Morcar, at Oxford, in 1015] Their supporters, trying to avenge their lords' deaths, were defeated and driven into the tower of St Frideswide's church, where, since they could not be driven out, they were burnt to death. Later the king repented, the filth was cleared away and the shrine restored. I have read an account which is contained in the archives of the church as a record of what had happened.

Henry of Huntingdon: Historia Anglorum (early 12th century)

[1002] With her arrival [Queen Emma], King Æthelred's pride increased and his faithlessness grew: in a treacherous plot, he ordered all the Danes who were living peacefully in England to be put to death on the same day, namely the feast of St Brice [13 November]. Concerning this crime, in my childhood I heard very old men say that the king had sent secret letters to every city, according to which the English either maimed all the unsuspecting Danes on the same day and hour with their swords, or, suddenly, at the same moment, captured them and destroyed them by fire.

'John of Wallingford' (13th century)

Thus did the Danes increase by degrees, till they oppressed the people of the land. During the whole of this period East Anglia was especially open to them, because it is opposite to their country, and the excellence of its parts gave them easy means of access or departure; so that, if they were diminished in number either by the effects of old age, or any accident, they could at once gain fresh recruits by this ready method of approach. They had also either seized, or prepared to seize, all the best towns in the land, and caused much trouble to the natives of the land; for they were wont, after the fashion of their country, to comb their hair every day, to bathe every Saturday, to change their garments often, and set off their persons by many such frivolous devices. In this manner they laid siege to the virtue of the married women, and persuaded the daughters even of the nobles to be their concubines. For these and other like causes there arose many quarells and wars in the realm. The king, however, smoothed the matter over, because the Danes were always in the wrong. At length, from the constant influx of their countrymen, they had so increased in numbers and strength, that they paid but littIe respect to the king; so that at last he was so provoked by the numerous complaints arising from their insolence, that he gave them all up to the English to be dealt with as they might think fit. But the plot did not tum out well, for not fearing the judgement of God, and counselling but badly for their own safety, they agreed together that each province should kill the Danes at that time resident within its limits; and they appointed a certain day on which they should rise up against them. This was on the Saturday, on which (as has been before said) the Danes are in the habit of bathing; and, accordingly, at the set time they were destroyed most ruthlessly, from the least even to the greatest. They spared neither sex nor age, destroying together with them those women of their own nation who had consented to intermix with the Danes, and the children who had sprung from that foul adultery. Some women had their breasts cut off; others were buried alive in the ground; while the children were dashed to pieces against posts and stones.The Danes themselves were so utterly destroyed that there survived no one to tell what had been done, with the single exception of twelve young men, who escaped from the slaughter in London, and, fleeing to the Thames, threw themselves into a small boat, and, seizing the oars, quickly rowed themselves out of sight, and when they came to the sea-coast, they exchanged it for a ship, and spreading sail as quickly as they could set off for Denmark.

Roger of Wendover (13th century)

In this year [1012] a certain Huna, King Æthelred's chief military commander, an undaunted and warlike man, beholding the insolence of the Danes, who after the establishment of peace had grown strong throughout the whole of England, presuming to violate and insult the wives and daughters of the nobles of his kingdom, came in much distress to the king and made his doleful complaint before him. Greatly moved thereat, the king, by the advice of the same Huna, sent letters into all parts of the kingdom, commanding all the people that on one day - the feast of St Brice the bishop - they should rise and put to death all the Danes settled in England, leaving none surviving, so that the whole English nation might once and for ever be freed from Danish oppression. And so the Danes, who a little before had made a league with the English, and had sworn to live peacably with them, were shamefully slain, and their wives and little ones dashed against the posts of their houses. The decree was mercilessly carried into effect in the city of London, insomuch that a number of Danes who had fled to a church for refuge, were all butchered before the very altars. But some Danish youths, flying on board a vessel, escaped to Denmark, and reported to King Swein the bloody end of his people. Moved to tears thereat, he called together all the nobles of his kingdom, and making known to them what had happened, inquired of them diligently what they advised to be done; whereupon they all with one acclamation determined that the blood of their kinsmen and friends should be revenged. Their fury was increased by the death of Gunnhild, sister of King Swein, who was slain in England on this occasion. For this Gunnhild had been married to Earl Pallig, a Danish nobleman, and coming to England in former years with her husband, had there embraced the faith of Christ and the sacrament of baptism. This discreet woman had mediated a peace between the Danes and English and had given herself, with her husband and only son, as a hostage to King Æthelred for its security. Having been committed by the king to the custody of Earl Eadric, atter a few days this traitor caused her husband and her son to . be cruelly slain in her presence with four lances, and lastly ordered the noble woman to be decapitated. Enduring with fortitude the terrors of death, Gunnhild neither grew pale at its approach, nor did she lose her serenity of countenance after her blood was spent; howbeit she confidently asserted in her last moments that the shedding her blood would be to the great damage of all England. For these causes, Swein, king of the Danes, a cruel and blood-thirsty man, eager for vengeance, assembled all his own forces, and sent messengers with letters to places out of his dominion, inviting such as were honest soldiers, desirous of gain and light of heart, to join in this expedition.