Many English toponyms have been corrupted and broken down over the years, due to language changes which have caused the original meanings to be lost.
Sometimes these meanings have remained clear to speakers of modern English (for instance Newcastle and Sevenoaks); more often, however, elucidating them requires the study of older languages.
As the names lost their original meanings either due to the introduction of a new language or linguistic drift, they gradually changed, or were appended with newer elements.
During the Iron Age, the population of Great Britain shared a culture with the Celtic peoples inhabiting western Europe.
[3] The evidence from this period, mainly in the form of place-names and personal names, makes it clear that a Celtic language, called Common Brittonic, was spoken across what came to be England by the Late Iron Age.
The principal substrate of British toponyms is thus Celtic in origin, and more specifically Brittonic ('British'), ancestral to modern Welsh and more distantly related to the Goidelic languages of Ireland and Scotland.
Often, these were simply a Latinisation of existing names, including Verulamium for Verlamion (St Albans) and Derventio for Derwent (Malton).
Following the end of the Roman Empire, several Germanic tribes living along the north sea coast began to migrate to Britain, variously displacing, intermarrying with, or ruling over local populations.
Due to this replacement of tongue and population growth, most settlement names in modern England are discernibly Old English in origin.
Since Old Norse had many similarities to Old English, there are also many hybrid English/Norse place-names in the Danelaw, the part of England that was under Danish rule for a time.
[11] Coates suggests that some British island and River names may derive from these languages, giving the English examples of Thanet, Scilly, Humber and Severn.
[11] There is also evidence that a pre-Celtic, but Indo-European, language provides the etymologies of various English rivers, as part of the theorised Old European hydronymy.
Some Latin elements are more recent still: Bognor Regis, for example, received its honorific suffix (meaning 'of the King') from George V after he convalesced there.
[18][20] Due to the Norman conquest, some place-names gained an additive, mainly a suffix, giving the names of their new owners: for example Grays Thurrock which is the rare prefix version and typical Stoke Mandeville; Stanton Lacy; Newport Pagnell.
In Cumbria, there remain a number of place-names from Cumbric, the former Brythonic language of this region, examples including Carlisle, Helvellyn and Blencathra.
Brythonic but non-Cornish place-names, sometimes showing Cornish or Welsh influence, are found in North Somerset and parts of Dorset.
For example, the names Howe and Greenhow (both in North Yorkshire) reflect the Old Norse word haugr meaning a hill or mound.