William the Conqueror

William the Conqueror, 19th century engraving, England
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William the Conqueror was a Duke of Normandy, who fought to regain his power over the duchy, establishing it as a powerful force in France, before completing the successful Norman Conquest of England.


William was born to Duke Robert I of Normandy – although he wasn’t Duke until his brother died - and his mistress Herleva c. 1028. There are various legends about her origins, but she was possibly noble. His mother had one more child with Robert ​and married a Norman noble called Herluin, with whom she had two further children, including Odo, later a bishop and regent of England. In 1035 Duke Robert died on pilgrimage, leaving William as his only son and designated heir: Norman lords had sworn to accept William as Robert’s heir, and the King of France had confirmed this. However, William was only eight, and illegitimate - he was known frequently as ‘The Bastard’ - so while the Norman aristocracy initially accepted him as ruler, they did so mindful of their own power. Thanks to still developing succession rights, illegitimacy was not yet a bar to power, but it did make the young William reliant on others.


Normandy was soon plunged into discord, as ducal authority broke down and all levels of the aristocracy began building their own castles and usurping the powers of William’s government. War was frequently fought between these nobles, and such was the chaos that three of William’s protectors were killed, as was his teacher. It is possible that William’s steward was killed while William slept in the same room. Herleva’s family provided the best shield. William began to play a direct role in Normandy’s affairs when he turned 15 in 1042, and for the next nine years, he forcefully regained royal rights and control, fighting a series of war against rebel nobles. There was vital support from Henry I of France, especially at the battle of Val-es-Dunes in 1047, when the Duke and his King defeated an alliance of Norman leaders. Historians believe that William learned a huge amount about warfare and government through this period of turmoil, and it left him determined to retain full control over his lands. It may also have left him ruthless and capable of brutality.

William also took steps to regain control by reforming the church, and he appointed one of his key allies to the Bishopric of Bayeux in 1049. This was Odo, William’s half-brother by Herleva, and he took the position aged only 16. Nevertheless, he proved a loyal and able servant, and the church grew strong under his control.

The Rise of Normandy

By the late 1040s the situation in Normandy had settled to the extent that William was able to take part in politics outside his lands, and he fought for Henry of France against the Geoffrey Martel, Count of Anjou, in Maine. Trouble soon returned at home, and William was forced to once more fight a rebellion, and a new dimension was added when Henry and Geoffrey allied against William. With a mixture of luck – the enemy forces outside Normandy did not coordinate with those in, although William’s alacrity contributed here – and tactical skill, William defeated them all. He also outlived Henry and Geoffrey, who died in 1060 and were succeeded by more congenial rulers, and William secured Maine by 1063.

He was accused of poisoning rivals to the region but this is widely believed to be just rumor. Nevertheless, it is interesting that he opened his attack on Maine by claiming the recently deceased Count Herbert of Maine had promised William his land should the count die without a son, and that Herbert had become a vassal of William’s in exchange for the county. William would claim a similar promise again shortly after, in England. By 1065, Normandy was settled and the lands surrounding it had been pacified, through politics, military action, and some lucky deaths. This left William as the dominant aristocrat in north France, and he was free to take on a grand project if one arose; it soon did.

William married in 1052/3, to the daughter of the Baldwin V of Flanders, even though the Pope had ruled the marriage as illegal due to consanguinity. It may have taken until 1059 for William to work his way back into the good graces of the papacy, although he may have done so very quickly – we have conflicting sources - and he founded two monasteries while doing so. He had four sons, three of whom would go on to rule.

The Crown of England

The link between the Norman and English ruling dynasties had started in 1002 with a marriage and had continued when the Edward – later known as ‘the Confessor’ – had fled from Cnut’s invading force and taken shelter at the Norman court. Edward had retaken the English throne but grew old and childless, and at some stage during the 1050s there may have been negotiations between Edward and William over the right of the latter to succeed, but it is unlikely. Historians don’t know for certain what really happened, but William claimed he had been promised the crown. He also claimed that another claimant, Harold Godwineson, the most powerful noble in England, had sworn an oath to support William’s claim while on a visit to Normandy. Norman sources support William, and Anglo-Saxons ones support Harold, who claimed Edward had really given Harold the throne as the king lay dying.

Either way, when Edward died in 1066 William claimed the throne and announced he would invade to take it off Harold and he had to persuade a council of Norman nobles who felt this was too risky a venture. William quickly gathered an invasion fleet which included noblemen from across France – a sign of William’s high reputation as a leader - and may have gained support from the Pope. Critically, he also took measures to ensure Normandy would remain loyal while he was absent, including giving key allies greater powers. The fleet tried to sail later that year, but weather conditions delayed it, and William eventually sailed on September 27th, landing the next day. Harold had been forced to march north to fight another invading claimant, Harald Hardrada, at Stamford Bridge.

Harald marched south and took up a defensive position at Hastings. William attacked, and the Battle of Hastings followed in which Harold and significant portions of the English aristocracy were killed. William followed the victory by intimidating the country, and he was able to be crowned King of England in London on Christmas Day.

King of England, Duke of Normandy

William adopted some of the government he found in England, such as the sophisticated Anglo-Saxon exchequer and laws, but he also imported large numbers of loyal men from the continent to both reward them and hold his new kingdom. William now had to crush rebellions in England, and on occasion did it brutally. Even so, after 1072 he spent the majority of his time back in Normandy, dealing with recalcitrant subjects there. The borders of Normandy proved problematic, and William had to deal with a new generation of warring neighbors and a stronger French king. Through a mixture of negotiation and warfare, he tried to secure the situation, with some successes.

There were more rebellions in England, including a conspiracy involving Waltheof, the last English earl, and when William had him executed there was great opposition; the chronicles like to use this as the start of a perceived decline in William’s fortunes. In 1076 William suffered his first major military defeat, to the King of France, at Dol. More problematic, William fell out with his eldest son Robert, who rebelled, raised an army, made allies of William’s enemies and started raiding Normandy. It is possible the father and son may even have fought in hand to hand in one battle. A peace was negotiated and Robert was confirmed as heir to Normandy. William also fell out with his brother, bishop and sometime regent Odo, who was arrested and imprisoned. Odo may have been about to bribe and threaten his way into the papacy, and if so William objected to the large number of troops Odo was planning to take from England to aid him.

While trying to retake Mantes he suffered an injury – possibly while on horseback - which proved fatal. On his deathbed William made a compromise, giving his son Robert his French lands and William Rufus England. He died on September 9th, 1087 aged 60. As he died he asked for prisoners to be released, all except Odo. William’s body was so fat it did not fit into the prepared tomb and burst out with a sickening smell.


William’s place in English history is assured, as he completed one of the few successful conquests of that island, and transforming the makeup of the aristocracy, the pattern of the land, and the nature of culture for centuries. Normans, and their French language and customs, dominated, even though William adopted much of the Anglo-Saxon machinery of government. England was also tied closely to France, and William transformed his duchy from anarchic into the most powerful north French holding, creating tensions between the crowns of England and France which would also last for centuries.

In the later years of his reign, William commissioned in England a survey of land use and value known as the Domesday Book, one of the key documents of the medieval era. He also bought the Norman church into England and, under the theological leadership of Lanfranc, changed the nature of English religion.

William was a physically imposing man, strong early on, but very fat in later life, which became a source of amusement to his enemies. He was notably pious but, in an age of common brutality, stood out for his cruelty. It’s been said he never killed a prisoner who might later be useful and was cunning, aggressive and devious. William was probably faithful in his marriage, and this may have been the consequence of shame he felt in his youth as an illegitimate son.

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Wilde, Robert. "William the Conqueror." ThoughtCo, Jul. 30, 2021, thoughtco.com/william-the-conqueror-1221082. Wilde, Robert. (2021, July 30). William the Conqueror. Retrieved from https://www.thoughtco.com/william-the-conqueror-1221082 Wilde, Robert. "William the Conqueror." ThoughtCo. https://www.thoughtco.com/william-the-conqueror-1221082 (accessed May 18, 2022).

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