The ancient Welsh patronymic naming system can cause significant problems for genealogists.
The old tendency to anglicise Welsh names can also present another hurdle for Welsh genealogists.
Patronymics describes the process of giving a child the father's given, or forename, as a surname. This means that a family's name changes in successive generations. The Welsh patronymic system describes family trees in terms of the male line only and records the family association in the 'ap' or 'ab' prefix ('ap' is a contraction of the Welsh word 'mab', which means son). For example, Rhys ap Dafydd translates as 'Rhys, son of David'. Modern Welsh surnames such as Powell, Price and Prichard are the result of this contraction and a progressive tendency to Anglicise Welsh names: under the patronymic system they would have been ap Hywel, ap Rhys and ap Richard.
This process of conversion to the system of fixed names in Wales began in the fifteenth century and continued through to the middle of the eighteenth century. The trend was stratified socially: the higher classes in society began the process, which then was passed on to the lower classes. Consequently, genealogists whose research has reached this period in Welsh history can sometimes find that their search grinds to a halt as family names disappear into the patronymic system of naming.
The range of Welsh surnames is very small, due in part to this process of conversion, but also because of the growing tendency to adopt English forenames (usually taken from Christian saints), particularly in towns on the Welsh borders. Names such as John, William, David and Hugh became Jones, Williams, Davis and Hughes. In north Wales, place names were frequently adopted, and in mid Wales families adopted nicknames for surnames. Jenkins is possibly derived from two different sources: as a corruption of a Flemish version of John, and as a result of the popularity of the name Ieuan in Wales during this period. Ieuan also gave rise to Evan(s) and Jones.
The way in which official records of births, marriages and deaths were kept also complicates the issue. The Act of Union (1536) stated that all official documentation in Wales was to be carried out in the English language. This meant that Welsh names were registered in an anglicised form. The process of civil registration in 1837 completed the long transition to fixed surnames. The traffic was not all one-way, though. The names of Welshmen who migrated to England were often transposed into English, so Ddu became Dee and Caradog became Craddock.
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