Duke of Normandy
It was not until the mid 1040's that William was old enough to rule unaided and at once he began campaigns against rebel Normans and neighbouring enemies. He quickly gained a ruthless reputation. A revolt erupted in 1047, led by Guy of Brionne, the son of the Count of Burgundy, William's cousin. William sought help from other Lords and King Henry of France to put the rebelion down. At the battle of Val es Dunes William defeated the rebels, but was lenient, only destroying their castles. Guy was allowed to return to Burgundy. In October 1049, William married Matilda the daughter of Count Baldwin of Flanders, one of his few allies. The marriage was against the wishes of the Pope who thought that Matilda and William were too closely related. William wanted the marriage for the important alliance with Flanders and also because he was in love with Matilda. The marriage was discussed by Pope Leo IX in Rheims. This caused some alarm, as it had not been for some time that a Pope had travelled to France to interfere with events.
In 1051 Edward the Confessor, the King of England was having problems restraining the Godwin family. In the hope that the Normans would assist him, Edward offered William, Duke of Normandy the right to claim the English throne after his death. Edward had no children and no direct heir. In 1066 just before his death, Edward changed his mind and offered the English throne to his wife's brother, Harold, Earl of Godwin. William had been visited by Harold earlier in 1064 and at a meeting it is suspected that Harold agreed to William's succession. When William learnt that Harold was to become king he was outraged and began invasion plans.
By August of 1066 the invasion fleet was ready, but the winds in the English Channel were not right and he had to delay sailing. This delay was fortunate for William because in July another invasion led by Harold Hardrada had begun in the north of England. This drew king Harold away from the south coast. King Harold fought and defeated Hardrada on 25th September at Stamford Bridge. At the same time, the winds on the Channel became favourable and William crossed to land without opposition at Pevensey. King Harold then marched his exhausted army back south to fight William.
As King of EnglandThe armies of William and Harold meet at Hastings on the 14th of October 1066. William was victorious and Harold was killed. After the battle there was little resistance and William was accepted as the new King. He was crowned at Westminster Abbey on 25th December 1066. For the first few years of his reign William spent time in Normandy and in England and while away he promoted his half brother Odo as his deputy in charge of English affairs. Not everyone in England was happy with the new Norman Kings and several revolts broke out. William was able to deal with each revolt in turn and soon began the construction of many castles to help subdue the rebels. William brought his Norman friends across the Channel with him and quickly began replacing the Bishops and Earls with his own men. The most famous Norman Bishop was Lanfranc who became the Archbishop of Canterbury.
Defending his Empire
From 1071 onwards, William had to contend with threats of invasion both against England, but also against his lands of Normandy. Threats from Swein of Denmark, The King of France and the Counts of Anjou and Flanders were a constant problem. William also had to content with his eldest son Robert, who was involved with William's enemies.
The Domesday Book
In December of 1085, William the Conqueror ordered the survey of his lands in Britain. The survey was given the name Domesday Book possible because of its similarity to the Last Judgement of Christ, or Domesday. A detailed record of ownership of land, types of land, numbers of people and their status, numbers of animals was undertaken. Details were not just required for that moment in time, but at the time of Edward the Confessor (1065) and at the time when the land was granted by William himself. Each shire was required to obtain and collate the information and any disputes were heard in a court with a jury of equal numbers of English and Normans. The survey was written up into two volumes and was held at the Winchester Treasury.
Whether this was the first survey of its type is unknown, but it is the first recorded survey. The reason why the survey was taken is not known either. After the Conquest the allocation of land had probably been chaotic and the survey could have been a method of sorting out the confusion and to prevent further disputes. Knowing how much workable land and working people there were would have also been useful for taxation and military purposes.
While fighting the King of France in Vexin in July 1087, William was injured and died from his injuries on 9th September. He was buried in the church of St. Stephen in Caen.