Michael Williams conducted a name analysis of the Monmouthshire town of Caerleon in his book Researching Local History: The Human Journey. His purpose was to study the relationship between traditional Welsh patronymics and the incursion of English surnames. Williams commenced with the town's baptismal parish register in 1700, and ended in 1899. (For completion chapel baptisms were also included)
For each block of 25 years, the following was collected:
From the resulting data, graphs were charted of:
The resulting graphs show that before 1750, Caerleon had a largely hereditary patronymic profile. On further local history research, a marked fluctuation in the graphs were accounted for by metal workers arriving from the West Midlands to work in a new iron forge and tin works in 1750-1760.
Michael Williams' study shows the importance of not treating surname analysis in isolation, but in conjuction with the history of a community.
(M Williams: Researching Local History: The Human Journey (Approaches to Local History series), Longman, Harlow 1996.)