Domesday
In 1080, Harald HÚn, king of Denmark had died. He was succeeded by his brother, Cnut (Cnut IV). The 'Anglo-Saxon Chronicle' entry for 1085 says:
"In this year men reported, and of a truth asserted, that Cnut, king of Denmark, son of King Swegn [Swein Estrithson], was coming hitherward, and was resolved to win this land, with the assistance of Robert, earl [count] of Flanders; for Cnut had [married] Robert's daughter....
William of Malmesbury: "... he [Cnut] prepared, as we have heard, more than a thousand vessels against England; his father-in-law, Robert le Frison, the possessor of six hundred more, supporting him ..."  According to saga, Cnut's brother-in-law, King Olaf III (Olaf 'Kyrre') of Norway, committed sixty ships to the fleet.
.... When William, King of England, who was then resident in Normandy (for he had both England and Normandy), understood this, he went into England ....
Florence of Worcester notes that it was "in the autumn" that William returned to England.
.... with so large an army of horse and foot, from France and Brittany, as never before sought this land; so that men wondered how this land could feed all that force. But the king had the army dispersed through all this land amongst his subjects ....
Florence of Worcester specifies: "his bishops, abbots, earls, barons, sheriffs and royal officers".
.... who fed them, each according to his quota of land. Men suffered much distress this year; and the king caused the land to be laid waste about the sea coast; that, if his foes came up, they might not have anything on which they could very readily seize. But when the king understood of a truth that his foes were impeded, and could not further their expedition, then let he some of the army go to their own land; but some he held in this land over the winter....
There was a dispute amongst the Danes, and the invasion fleet dispersed. The dispute escalated, however, and, on 10th July 1086, Cnut was killed by rebels, in the Church of St.Alban at Odense. Cnut (St.Knud) was canonised, in 1101.
.... Then, at the midwinter [1085], was the king in Glocester with his council, and held there his court five days. And afterwards the archbishop and clergy had a synod three days... After this had the king a large meeting, and very deep consultation with his council, about this land; how it was occupied, and by what sort of men. Then sent he his men over all England into each shire; commissioning them to find out how many hundreds of hides were in the shire, what land the king himself had, and what stock upon the land; or what dues he ought to have by the year from the shire. Also he commissioned them to record in writing how much land his archbishops had, and his diocesan bishops, and his abbots, and his earls; and - though I tell it at too great length - what, or how much, each man had, who was an occupier of land in England, either in land or in stock, and how much money it was worth. So very narrowly, indeed, did he commission them to trace it out, that there was not one single hide, nor a yard of land, nay, moreover (it is shameful to tell, though he thought it no shame to do it), not even an ox, nor a cow, nor a swine was there left, that was not set down in his writ. And all the recorded particulars were afterwards brought to him."
The product of this great survey became known as the 'Domesday Book'.
The 'Anglo-Saxon Chronicle' continues:
"This year [1086] the king wore his crown, and held his court, in Winchester at Easter; and he so arranged, that he was by the Pentecost at Westminster, and dubbed his son Henry a knight there. Afterwards he moved about so that he came by Lammas [1st August] to Salisbury; where he was met by his councillors; and all the landsmen that were of any account over all England, no matter which man's men they were ....
Once again, Florence of Worcester specifies: "his archbishops, bishops, abbots, earls, barons, sheriffs, with their knights"."
.... and they all bowed themselves before him, and became his men, and swore him oaths of allegiance that they would against all other men be faithful to him....
This 'Salisbury Oath' has been the subject of much discussion. In 'Anglo-Saxon England', Sir Frank Stenton opines: "The precedent which it set was momentous in the development of the English feudal state. For it gave public and solemn expression to the principle that the fealty which the tenant owed to his immediate lord must not be allowed to conflict with the fealty which, like all subjects, he owed to his sovereign."
.... Thence he proceeded into the Isle of Wight; because he wished to go into Normandy, and so he afterwards did; though he first did according to his custom; he collected a very large sum from his people, wherever he could make any demand, whether with justice or otherwise. Then he went into Normandy; and Edgar the Ătheling, the relation of King Edward, revolted from him, for he received not much honour from him; but may the Almighty God give him honour hereafter....
Florence of Worcester: "... Edgar, Štheling, having obtained permission of the king, went over sea with two hundred knights, and proceeded to Apulia ..."
.... And Christina, the sister of the Štheling, went into the monastery of Romsey, and received the holy veil. And the same year there was a very heavy season, and a laborious and sorrowful year in England, in murrain of cattle, and corn and fruits were at a stand, and so much untowardness in the weather, as a man may not easily think; so tremendous was the thunder and lightning, that it killed many men; and it continually grew worse and worse with men. May God Almighty better it whenever it be his will."
"After the birth of our Lord and Saviour Christ, one thousand and eighty-seven winters [Note]; in the one and twentieth year after William began to govern and direct England, as God granted him, was a very heavy and pestilent season in this land. Such a sickness came on men, that full nigh every other man was in the worst disorder - that is the fever; and that so dreadfully, that many men died in the disorder. Afterwards came, through the badness of the weather as we before mentioned, so great a famine over all England, that many hundreds of men died a miserable death through hunger. Alas! how wretched and how rueful a time was there! Then the poor wretches lay full nigh driven to death, and afterwards came sharp hunger, and dispatched them entirely!
Who will not be penetrated with grief at such a season? Or who is so hardhearted as not to weep at such misfortune? Yet such things happen for folks' sins, that they will not love God and righteousness. So it was in those days, that little righteousness was in this land with any men, but with the monks alone - wherever they fared well. The king and the head men loved much, and overmuch, covetousness in gold and in silver; and cared not how sinfully it was got, provided it came to them. The king let his land at as high a rate as he possibly could; then came some other person, and bade more than the former one gave, and the king let it to the men that bade him more. Then came the third, and bade yet more; and the king let it to the hand of the man that bade him most of all: and he cared not how very sinfully the reeves got it of wretched men, nor how many unlawful deeds they did; but the more men spake about right law, the more unlawfully they acted. They erected unjust tolls, and many other unjust things they did, that are difficult to reckon.
Also in the same year, before harvest, the holy minster of St.Paul, the episcopal see in London, was completely burned, with many other minsters, and the greatest part and the noblest of the whole city. So also, about the same time, full nigh each chief-town in all England was entirely burned. Alas! rueful and woeful was the fate of the year that brought forth so many misfortunes.
In the same year also, before the Assumption of St.Mary [15th August], King William went from Normandy into France with an army, and made war upon his own lord Philip, the king, and slew many of his men, and burned the town of Mantes, and all the holy minsters that were in the town; and two holy men that served God, leading the life of anchorites, were burned therein. This being thus done, King William returned to Normandy. Rueful was the thing he did; but a more rueful him befel. How more rueful? He fell sick, and it dreadfully ailed him....
Florence of Worcester: "... on the journey a dreadful disease of the bowels seized him, which grew more and more serious from day to day [Note]. Now when, as his sickness became worse, he perceived that the day of his death was near, he released his brother Odo, bishop of Bayeux, earls Morkar [Morcar] and Roger, Siward, surnamed Barn, and Wulnoth [Wulfnoth], brother of king Harold, whom he had kept in confinement from boyhood [Note], and all whom he had delivered into custody in England or in Normandy."  Orderic Vitalis says that, before they were released, King William, not unreasonably, insisted the prisoners: "... take an oath to my ministers, for the security of the state, that they will use every means to preserve the peace both in Normandy and in England, and will steadfastly resist the enemies of tranquility to the utmost of their power."  According to Orderic, the king had initially excluded Odo from his amnesty, but eventually gave way (against his own better judgement) to the entreaties of the bishop's friends.  "He [King William] summoned to his side his sons William Rufus and Henry, who were in attendance on him with some of his friends, and gave them many wise and prudent directions for the regulation of his states. Robert, his eldest son, had long since entered on a course of repeated quarrels with his father, and had recently taken umbrage in consequence of some new follies, and retired to the court of the king of France."  Nevertheless, William acknowledged that it was Robert's right to rule Normandy. Orderic puts words into his mouth: "I granted the dukedom of Normandy to my son Robert, because he was the eldest, before I fought against Harold on the heath of Senlac. He has already received the homage of nearly all the barons of this land. The grant thus made and ratified I cannot annul. But I know for certain that the country which is subject to his dominion will be truly wretched."
.... What shall I say? Sharp death, that passes by neither rich men nor poor, seized him also. He died in Normandy, on the next day after the Nativity of St.Mary [i.e. on 9th September] ....
Orderic Vitalis: "... the king waking just when the sun was beginning to shed his rays on the earth, heard the sound of the great bell of the cathedral of Rouen. On his inquiring what it meant, his attendants replied: "My Lord, the bell is tolling for primes in the church of St.Mary." Then the king, raised his eyes to heaven with deep devotion, and lifting up his hands said: "I commend myself to Mary, the holy mother of God, my heavenly mistress, that by her blessed intercession I may be reconciled to her well beloved Son, our Lord Jesus Christ." Having said this he instantly expired."
.... and he was buried at Caen in St.Stephen's minster, which he had formerly reared, and afterwards endowed with manifold gifts.
Alas! how false and how uncertain is this world's prosperity! He that was before a powerful king, and lord of many lands, had not then of all his land more than a space of seven feet! and he that was formerly enshrouded in gold and gems, lay there covered with earth!
He left behind him three sons; the eldest, called Robert, who was earl in Normandy after him; the second, called William, who wore the crown after him in England; and the third, called Henry, to whom his father bequeathed immense treasure.
If any person wishes to know what kind of man he was, or what honour he had, or of how many lands he was lord, then will we write about him as well as we understand him: we who often looked upon him, and lived sometime in his court.
According to the tradition preserved in the 'Chronicle of Battle Abbey', William, before the battle of Hastings, vowed that, should God grant him victory, he would build a monastery on the battlefield. His oath was heard by, a monk of Marmoutier, William 'the Smith':
"The illustrious King William was fully occupied ... and although he never actually forgot his vow ... he put off its fulfilment (amongst other things) for a long time. However, his conscience was urging him from within, while from without the monk William 'the Smith' kept reminding him assiduously, no easy thing to do. At last, since the monk was nearby, the king committed the building of the abbey to him as he had wished, commanding him to fetch some brothers from his own church and set speedily in hand the establishment of a suitable monastery on the battlefield. Accepting with alacrity, the monk went quickly to Marmoutier and brought with him into England four monks from there ... They studied the battlefield and decided that it seemed hardly suitable for so outstanding a building... Accordingly, when the solicitous king inquired meanwhile about the progress of the building, it was intimated to him by these brethren that the place where he had decided to have the church built was on a hill, and so dry of soil, and quite without springs, and that for so great a construction a more likely place nearby should be substituted, if it pleased him. When the king heard this he refused angrily and ordered them to lay the foundation of the church speedily and on the very spot where his enemy had fallen and the victory been won... And so at length, the foundations were laid of what was in those days thought an outstanding building, and they prudently erected the high altar as the king had commanded, on the very place where Harold's emblem, which they call a 'standard', was seen to have fallen."
This King William then that we speak about was a very wise man, and very powerful; more noble and stronger than any of his predecessors were. He was mild to the good men that loved God, and beyond all measure severe to the men that gainsayed his will. On that same spot where God granted him that he should gain England, he reared a mighty minster, and set monks therein, and well endowed it [see left]. In his days was the great minster in Canterbury built [Add.12], and also very many others over all England. This land was moreover well filled with monks, who modelled their lives after the rule of St.Benedict; and such was the state of Christianity in his time, that each man followed what belonged to his order - he that would.
He was also very dignified. Thrice he wore his crown each year, as oft as he was in England. At Easter he wore it in Winchester, at Pentecost in Westminster, at midwinter in Gloucester. And then were with him all the powerful men over all England; archbishops and diocesan bishops, abbots and earls, thegns and knights. So very stern was he also and hot, that no man durst do anything against his will. He had earls in his custody, who acted against his will. Bishops he hurled from their bishoprics, and abbots from their abbacies; and thegns into prison. At length he spared not his own brother Odo, who was a very powerful bishop in Normandy - at Bayeux was his episcopal stall - and he was the foremost man of all next to the king. He had an earldom in England; and when the king was in Normandy, then was he the mightiest man in this land. Him he confined in prison. But amongst other things is not to be forgotten that good peace that he made in this land; so that a man of any account might go over his kingdom unhurt with his bosom full of gold. No man durst slay another, had he never so much evil done to the other; and if any common man lay with a woman against her will, he soon lost the limb that he played with.
William of Malmesbury: "He was of moderate stature, extraordinary corpulence, and fierce countenance; his forehead was bare of hair; he was of such great strength of arm that it was often matter of surprise that no one was able to draw his bow, which he himself could bend when his horse was at full gallop; he was majestic, whether sitting or standing, although the protuberance of his belly deformed the dignity of his appearance; of excellent health, so that he was never confined with any dangerous disorder, except at the last ..."
He truly reigned over England; and by his capacity so thoroughly surveyed it, that there was not a hide of land in England that he wist not who had it, or what it was worth, and afterwards set it down in his book. Wales was in his power; and he wrought castles therein; and he entirely controlled that race of men. So also he subdued Scotland to himself, by his great strength. As to Normandy, that was his native land; but he reigned also over the earldom called Maine; and if he might have yet lived two years more, he would have won Ireland by his prudence, and without any weapons. Assuredly in his time had men much labour, and very many insults.
Castles he had built,
and wretched men very much oppressed.
The king himself was so very stark;
and extorted from his subjects many marks
of gold, and many hundred pounds of silver;
that he took by weight, and with great unright,
from his people with little need.
Into covetousness did he fall,
and greediness he loved above all.
He made many deer-parks;
and he established laws therewith;
so that whosoever slew a hart, or a hind,
should be made blind.
As he forbade men to kill the harts, so also the boars;
and he loved the stags as much
as if he were their father.  [Add.13]
Likewise he decreed by the hares, that they should go free.
His magnates lamented it, and wretched men murmured at it.
But he was so stern, that he cared nothing for the hostility of them all;
for they must entirely follow the king's will
if they would live or have land -
land or property, or, indeed, his favours.
Alas! woe, that any man should be so proud,
puff himself up, and boast o'er all men.
May the Almighty God show mercy to his soul,
and grant him forgiveness of his sins!
These things have we written concerning him, both good and evil; that men may choose the good after their goodness, and flee from the evil entirely, and go in the way that leadeth us to the kingdom of heaven."
Postscript    
Translations:
'Chronicle of Battle Abbey' by Eleanor Searle
Orderic Vitalis 'Historia Ecclesiastica' by Thomas Forester
Eadmer 'Historia Novorum in Anglia' by Geoffrey Bosanquet
'Anglo-Saxon Chronicle' based on that by Rev. James Ingram/Dr. J.A. Giles
William of Malmesbury 'Gesta Regum Anglorum' by Rev. J. Sharpe, revised by Rev. J. Stevenson
Florence of Worcester 'Chronicon ex Chronicis' edited and in part translated by Joseph Stevenson