Hywel’s name is associated with the laws of Medieval Wales, which are commonly known as the Laws of Hywel Dda (Welsh: Cyfraith Hywel). None of the law manuscripts can be dated to Hywel’s time, but Hywel’s name is mentioned in the prologues to the laws. These describe how Hywel gathered expert lawyers and priests from each commote in Wales together in Tŷ Gwyn ar Daf (which is thought to have been close to Whitland, Carmarthenshire) in order to revise and codify the Laws of Wales. The story in the prologues lengthens with time, with more details in the later versions of the prologue. It seems highly unlikely that this meeting actually took place, with the purpose of the prologues being to emphasize the royal and Christian origin and background to the laws, and that in the face of criticism of the laws from outside Wales especially during John Peckham’s period as Archbishop of Canterbury. Nevertheless, his name continued to be associated with Welsh law which remained in active use throughout Wales until the appointed date of implementation of the Laws in Wales Acts 1535–1542 of Henry VIII of England who asserted his royal descent by blood-line from Rhodri Mawr via Hywel Dda.