King Edward I issued the Statute of Wales (sometimes referred to as the Statute of Rhuddlan) in 1284 as part of his program of subjugating Wales to English law. For Prince Llywelyn ap Gruffydd, and his people, being able to live under Welsh law had been a primary concern and one of the most compelling reasons to war with England. Edward, knowing this, saw to it that the Welsh laws were overthrown, and this act was not repealed for centuries. It was comprehensive and complete–the most comprehensive any King issued during the middle ages (Bowen 1908).
To download your own copy: http://www.archive.org/details/statuteswales01bowegoog
This site states: “At the Statute of Rhuddlan, 1284, Wales was divided up into English counties; the English court pattern set firmly in place, and for all intents and purposes, Wales ceased to exist as a political unit. The situation seemed permanent when Edward followed up his castle building program by his completion of Caernarfon, Conwy and Harlech. In 1300, Edward made his son (born at Caernarfon castle, in that mighty fortress overlooking the Menai Straits in Gwynedd) ‘Prince of Wales.'”
In summary, the Statute instated these laws:
1. Wales was annexed to the Crown of England
2. Divided Wales into counties and appointed officers, controlled by the King
3. Created the office of “Sheriff” and regulated the matter of the courts, abrogating Welsh law in this matter.
4. Created laws regarding debt, laws, and attorneys, inquests, pleas, trials, and juries, all in accordance with English common law.
5. Established laws of dower for women (for which there was no formal arrangement under Welsh law) and inheritance, according to English common law. He specifically forbade ‘bastards’ to inherit, as had been customary under Welsh law.