After the success of the Normans in 1066 at the Battle of Hastings, they sought to impose Norman rule throughout England and Wales. One way of demonstrating Norman supremacy over the conquered English was to impose their own names on places that had English names or variants from the Celts etc. For such a warlike people, one of the reasons the Normans changed some place names was a simple dislike for a name that they considered unpleasant. Other places were given a name for their beauty.
The Vikings raided and also colonised many areas of Northern France though they are most associated with the region of Normandy. However, many years later those who ruled Normandy had no intention of merely using the language of someone else in their conquered territories. As conquerors of England the Normans also wanted to make their mark on the country and they effectively introduced a new language to the land. It seems that the Normans had difficulty pronouncing certain place names, so they simply dispensed with them and changed them into place names that they could pronounce with ease. This is most clear in the changes to places such as Nottingham and Durham.
For years Nottingham had been 'Snotingaham' - 'the settlement of Snot'. However, with seemingly a dislike of pronouncing the letter 's', it was simply dropped to give the familiar name of today.
Cambridge endured a similar major change. Before the Normans arrived the town was known as 'Grantebrige'. Dunholm changed to Durelme to Dureaume to Durham.
Another explanation that has been put forward is that the Normans simply disliked some of the place names in their newly conquered territory and changed them into something more acceptable. What was Fulepet (Filthy Hole) in Essex was changed to Beaumont (Fair Hill); what had been Merdegrave in Leicestershire became Belgrave.
If the Normans liked a place, they frequently gave it a prefix of 'Beau' and 'Bel'. This may simply have been in appreciation of a place's scenic beauty. Beachy Head in East Sussex would be an example of this - 'fine headland'. Beaulieu in Hampshire means 'fair/fine place'. Belvoir in Leicestershire mean 'fine view'. It is ironic that a society that had a reputation for producing fearsome warriors also had a eye for fine scenery.
The Normans also used the names of great monasteries in Normandy for place names in England. Charterhouse on Mendip in Somerset was named after the great monastic house at Chartreuse. The great abbey at Rievaulx in Yorkshire seemingly comes from 'the valley of the River Rye'. Also in Yorkshire, Pontefract got its name changed from Pomfret so that it was closer to the Norman word for bridge. As the Normans wrote in Latin, the written form was Pontefracto (broken bridge), which became Pontefract when spoken.
The use of feudal service by the Normans once they had asserted their authority over England also led to the creation of place names that represented the family that was most dominant in any particular area. Manorial names were similar in their intent to those used by the Anglo-Saxons, though a lot more colourful. Ashby-de-la-Zouch has a French input in the 'de-la' while the Ashby would have come from a previous era. However, the family with the manorial rights to the area belonged to the de la Zuche family. The adoption of the surname was an emphatic way of asserting your family's manorial rights over the area. The Busard family was the most powerful in the area where Leighton Buzzard has developed. Tooting Bec was owned by the Abbey of Bech as is stated in the Domesday Book. Those families that had not only been loyal to William I but had also fought well for him were remembered when England was carved up to reward these families. While a local place name may still have had some vestige of Anglo-Saxon, Celtic or Roman to it, those who were given manorial rights also sealed their place in English society by adding their name to it. Hurstpierpoint in West Sussex would have had the 'hurst' before the 1066 Conquest. However the de Pierpoint family added their surname to it. The same occurred in Herstmonceux when the Monceux family did likewise.