I thought this might help researching welsh ancestors. When I started researching my grandfather's family, I didn't know about the Welsh Patronymic naming system. My grandfather's father was Rowland Williams, so my grandfather's surname became Rowlands. I found this out from a researcher in Wales. The Welsh used an ancient PATRONYMIC naming system whereby the children of a marriage took their Father's forename as their surname. As a result surnames were not fixed and changed from generation to generation. It works like this: Evan son of Thomas William would be known as Evan Thomas Evan's son, John would be John Evan John's son Rees would be Rees John Rees's son, David, would be David Rees David's son, James, would be James David If James then decided to abandon patronymics, he might retain the name David as his fixed surname or he might change it to Davies/Davis both of which imply 'son of' David.