The group of six Anglican kingdoms—Kent, Sussex, Wessex, East Anglia, Essex, Northumbria, and Mercia—is known to historians as the Heptarchy.

Mercia has been in conflict with Northumbria since at least 633, when Penda of Mercia defeated and killed Edwin of Northumbria at the Battle of Hatfield Chase.

However, there have been diplomatic marriages between the two kingdoms: Æthelred's sister Cyneburh had married Alhfrith, a son of Oswiu of Northumbria, and both Æthelred and his brother Peada had married daughters of Oswiu.

Cyneburh's marriage to Alhfrith had taken place in the early 650s, and Peada's marriage, to Ealhflæd, had followed shortly afterwards; Æthelred's marriage, to Osthryth, is of unknown date but must have occurred before 679, since Bede mentions it in describing the Battle of the Trent, which takes place in this year.

Bede does not mention the cause of the battle, simply saying that it occurred in the ninth year of Ecgfrith's reign.

He is more informative on the outcome.

Ælfwine, the young subking of Deira, was killed; Ælfwine was brother to Osthryth and Ecgfrith, and was well liked in both Mercia and Northumbria since Æthelred's marriage to Osthryth.

His death according to Bede threatened to cause further strife between the two kingdoms, but Theodore, the Archbishop of Canterbury, intervened.

Æthelred takes possession of Lindsey again after the battle; the change in control this time will be lasting, and Lindsey will remain part of Mercia until the Viking invasion of the ninth century remakes the map of England.

Significant parts of northeastern England, formerly Northumbria, are under the control of Danish Vikings after successful raids.

Danish attacks into central England had been resisted and effectively reduced by Alfred the Great, to the point where his son, King Edward of Wessex, can launch offensive attacks against the foreigners.

Edward is allied with the Mercians under his sister Æthelfleda, and their combined forces ware formidable.

The allies in 909 launch a five-week campaign against Lindsey and successfully capture the relics of Saint Oswald of Northumbria.

…the Conqueror turns southwards and arrives at the Roman and Viking city of Lincoln.

When William reaches Lincoln (one of the country's major settlements), he finds a Viking commercial and trading center with a population of six thousand to eight thousand.

The remains of the old Roman walled fortress located sixty meters (two hundred feet) above the countryside to the south and west, proves an ideal strategic position to construct a new castle.

Also, Lincoln represents a vital strategic crossroads of the following routes (largely the same routes which influenced the siting of the Roman fort).

A castle here could guard several of the main strategic routes and form part of a network of strongholds of the Norman kingdom, in Danish Mercia, roughly the area of the country that is today referred to as the East Midlands, to control the country internally.

Also (in the case of the Wolds) it could form a center from which troops could be sent to repel Scandinavian landings anywhere on the coast from the Trent to the Welland, to a large extent, by using the roads which the Romans had constructed for the same purpose.

The Domesday Survey of 1086 directly records forty-eight castles in England, with two in Lincolnshire including one in the county town.

Building a castle within an existing settlement sometimes meant existing structures had to be removed, and of the castles noted in the Domesday Book, thirteen included references to property being destroyed to make way for the castle.

In Lincoln’s case 166 “unoccupied residences” are pulled down to clear the area on which the castle is to be built.

Work on the new fortification is completed in 1068.

It is probable that at first a wooden keep was constructed which will later be replaced with a much stronger stone one.

Lincoln Castle is very unusual in having two mottes, the only other surviving example of such a design being at Lewes.

To the south, where the Roman wall stands on the edge of a steep slope, it is retained partially as a curtain wall and partially as a revetment retaining the mottes.

In the west, where the ground is more level, the Roman wall is buried within an earth rampart and extended upward to form the Norman castle wall.

…Lincoln.

The Jews tend to settle in large towns and commercial centers, close to the royal castle for protection against the sheriff.

The bishopric of Remigius de Fécamp, Bishop of Lincoln, is the largest in England, and one of the largest in the western Church.

It encompasses what had originally been three different bishoprics—that of Dorchester, Leicester and Lindsey, which had been combined together by about 1010.

Normally considered part of the Province of Canterbury, the Archbishops of York had long claimed it as part of their province due to Lindsey having been converted by Paulinus of York, the first Bishop of York.

Included within Remigius' diocese are a number of monasteries, including the wealthy ones of Ely Abbey, Peterborough Abbey, Ramsey Abbey and Thorney Abbey.

One difficulty with the diocese is that Dorchester is in the southern part of the large diocese, which makes administration difficult.

Another issue is that Dorchester is a very small town, but there is a large town in the diocese—Lincoln, which probably numbers around sixty-five hundred inhabitants.

Remigius had begun the construction of Lincoln Cathedral in the mid 1070s, modeling it after the cathedral at Rouen as well as the abbey church of St Etienne, Caen.

The tower he constructed, which is now incorporated into the west front of the Cathedral, may have been constructed as a keep tower.

Little now remains of Remigius' construction, just the tower which has been greatly altered from the original design by the addition of three porches.

Along with building a new cathedral, Remigius also has organized the cathedral chapter, or the clergy that serves the new church.

At Lincoln, Remigius set sup a chapter that is composed of secular clergy, rather than one composed of monks, which some of the other new cathedrals founded after the Norman Conquest use.

This is an unusual choice, as Remigius himself is a monk, and many of the new monastic cathedral chapters have been founded by monks, but the sheer size of the diocese requires large numbers of clergy to fully staff its functions.

Monks in the required numbers would have been difficult to find.

Bishop Remigius dies on May 9, 1092, two days before Lincoln Cathedral is consecrated.

The forces of King Stephen of England have been besieging Lincoln Castle but are themselves attacked by a relief force loyal to Empress Matilda and commanded by Robert, first Earl of Gloucester, Matilda's half-brother.

The Angevin army consists of the divisions of Robert's men, those of Ranulf, Earl of Chester and those disinherited by Stephen, while on the flank is a mass of Welsh troops led by Madog ap Maredudd, Lord of Powys, and Cadwaladr ap Gruffydd.

Cadwaladr is the brother of Owain, Prince of Gwynedd, but Owain does not support any side in The Anarchy.

Stephen’s force include William of Ypres; Simon of Senlis; Gilbert of Hertford; William of Aumale, Alan of Richmond and Hugh Bigod but is markedly short of cavalry.

As soon as the battle is joined, the majority of the leading magnates flee.

Even as the royal troops listen to the exhortations of Stephen's lieutenant, Baldwin fitz Gilbert, the advancing enemy is heard and soon the disinherited Angevin knights charge the cavalry of the five earls.

On the left Earl William Aumale of York and William Ypres charge and smash the poorly armed Welsh division but are themselves in turn routed by the well-ordered military might of Earl Ranulf.

The earls, outnumbered and outfought, are soon put to flight and many of their men are killed and captured.

King Stephen and his knights are rapidly surrounded by the Angevin force.

The rest of his division fights on with no hope of escape until all are killed or had surrendered.

Baldwin fitz Richard and Richard fitz Urse are taken prisoner.

Stephen's forces are defeated after fierce fighting in the city's streets.

Stephen himself is captured and taken to Bristol, where he was imprisoned.

Other important magnates captured with the king are Baldwin fitz Gilbert; Bernard de Balliol, Roger de Mowbray; Richard de Courcy; William Peverel of Nottingham; Gilbert de Gant; Ingelram de Say; Ilbert de Lacy and Richard fitz Urse, all men of respected baronial families; it had only been the Earls who had fled.

Lincoln had grown to be one of the wealthiest towns in England by 1150.

The basis of the economy is cloth and wool, exported to Flanders; Lincoln weavers had set up a guild in 1130 to produce Lincoln Cloth, especially the fine dyed 'scarlet' and 'green', the reputation of which will later be enhanced by Robin Hood wearing woolens of Lincoln green.

The bishops of Lincoln are among the magnates of medieval England: Lincolnshire, the largest diocese, has more monasteries than the rest of England put together, and the diocese is supported by large estates outside the county.

Lincoln is home to one of the five most important Jewish communities in England, well established before it is officially noted in 1154.

Aaron of Lincoln, reputedly the richest man in England, dies in 1186, leaving an estate over fifteen thousand pounds, which Henry II promptly seizes.

Aaron had such vast sums owed to him that the royal officials set up a special branch of the exchequer called the “exchequer of Aaron” (Scaccarium Aaronis) to deal with it.

Some of his debtors include the King of Scotland, the Archbishop of Canterbury, the Count of Brittany and many other nobles.

…John travels north to relieve the rebel siege at Lincoln and back east to …