Cadell was one of the sons of Rhodri the Great , and his inheritance was the southern part of his father's principality, namely Seisyllwg ( Ceredigion and Ystrad Tywi ). He bequeathed this to his two sons Hywel and Clydog , and on the latter's death in the year 920 Hywel took possession of the whole. He m. Elen , daughter of Llywarch ap Hyfaidd of Dyfed , who brought him Dyfed (modern Pembrokeshire ) as her dower — for Llywarch was, in all probability, the last prince of Dyfed . The prince of Gwynedd was Idwal Foel who also probably ruled over Powys . Idwal was killed in battle with the English in the year 942 and, although he had sons, Hywel took possession of all his territory. He thus became ‘ king of all Wales ’ although Morgannwg and Gwent continued to have independent sovereigns.
He succeeded throughout his life in maintaining peace with the English kings by submitting to them. In 918 he, Clydog his brother, and Idwal Foel did homage to Edward , son of Alfred the Great , and about 926 he and Owain of Gwent journeyed to Hereford to acknowledge the overlordship of Athelstan . His name is frequently mentioned in the English charters as a vassal king and there is little doubt that from time to time he visited the Wessex court . For all that, he was sufficiently independent to mint his own silver pennies and, as far as is known, he is the only Welsh prince to have done this.
His pilgrimage to Rome in 928 was one of the outstanding incidents in his life. It has been suggested that in this respect he was only following Alfred 's example and it may well be that it was Alfred 's work in England which induced him to undertake his most important task, the codification of the jumble of laws and customs prevailing in his kingdom . There can be no doubt that he was confirmed in his resolution by what he had seen on his travels.
The earliest extant manuscript of the ‘ Laws of Hywel the Good ’ dates from the last quarter of the 12th cent , but all the manuscripts agree that the laws were framed by his command and under his authority. They agree, too, as to the method adopted by him for carrying out the undertaking, namely the summoning of six representatives from each commote in his principality to a great conference at ‘ Ty Gwyn ar Daf in Dyfed ,’ (later on, an abbey was to rise near the spot and the Welsh name for the village of Whitland is still ‘ Yr Hen Dy Gwyn .’) This took place some time between 942 and 950 — perhaps about 945 .
We do not rightly know what were the contents of the book of the law as devised at the White House . In the 19th cent. Aneurin Owen discovered that the earliest manuscripts should be separated into three distinct ‘codes’ differing materially one from the other. Between the 10th and 12th cents. these differences grew, for the unity of Hywel 's kingdom did not survive his death in 950 . It is considered that the ‘ Code of Dyfed ’ (The Book of Blegywryd according to the classification of A. W. Wade-Evans ) is the one which has preserved most accurately the contents and the arrangement of the original. This ‘code’ and some other manuscripts mention Blegywryd as the man chosen by the king with ‘ twelve of his wisest lieges to determine and expound to him and his kingdom the laws and customs in their perfection and as near as may be to truth and justice .’ Moreover, it is said that the king commanded that ‘ they be written in three parts: firstly, the law of his daily court; secondly the law of the land; and thirdly, the custom of each of them. ’ Three ‘books’ of the law were to be made i.e. three copies: ‘ one for his daily court wherever he should be; one for the court at Dynevor ; and the third for the court at Aberffraw ; so that the three parts of Wales , Gwynedd , Powys , and the South, should have the authority of the law constantly and readily at hand. And, following the advice of those wise men, some of the old laws were confirmed, some were amended, while some were repealed in. their entirety and new laws substituted for them. ’
The excellence of these laws must be attributed to the wisdom and scholarship of Blegywryd and his colleagues, but it is only fair to assume that the unification and orderly arrangement of the rules governing life in the different provinces which he had fused into one kingdom was Hywel 's own conception. His renown is based on his work as a legislator and it may safely be claimed that, more than anything else, Hywel 's law was responsible for the consciousness of national unity prevalent among the Welsh of the Middle Ages .
[Hywel d. in 949 or 950 ; Harl. MS. 3859 enters it under the year corresponding to 950.]
Professor Stephen Joseph Williams, D.Litt., (1896-1992), Swansea
Published date: 1959