lands of Garth Madrun, which became known as Brycheiniog, after him. Brychan's eldest son (or grandson, depending on which manuscripts are reliable), Rhain Dremrudd (i.e. Rhain the red-faced), founded a dynasty which ruled the kingdom uninterrupted until the mid 7th century; manuscripts list his descendants (and successors) as: Rhigeneu ap Rhain Llywarch ap Rhygeneu Idwallon ap Llywarch. Rhiwallon ap Idwallon In the time of Idwallon, the aggressive Cynan Garwyn (king of Powys) invaded a number of lands, including Brycheiniog. Rhiwallon succeeded due to the subsequent collapse of Powysian power, under pressure from Dogfeiling, and the extreme youth of Cynan's later successor. Union with Dyfed Rhiwallon is the last direct male descendant of Brychan reported by any historic manuscript. His daughter, Ceindrych, married Cloten, the king of Dyfed. This 7th century marriage united the kingdom of Brycheiniog with Dyfed (which at that time bordered it), a union which lasted for about a century (though parts of Brycheiniog may have been granted out, from time to time, as lordships for younger sons). In the mid 8th century, Seisyll (king of Ceredigion) invaded, conquering Ystrad Tywi, and thus physically cleaving apart Dyfed and Brycheiniog. Rhain ap Cadwgan, great-grandson of Cloten and king of Dyfed-Brycheiniog, initially attempted to retain the union; the surviving parts were consequently known as Rhainwg. The impracticalities of ruling two regions physically separated by a rival kingdom meant that Rhain's brother, Awst, was eventually made governor of Brycheiniog, while Rhain now directly ruled only Dyfed. Following the death of Rhain and Awst, Rhain's son Tewdwr challenged the authority of Awst's son Elwystl. According to the Book of Llandaff, they were persuaded to divide Brycheiniog between them, swearing on the altar of Llandaff Cathedral to keep to this settlement. Soon after, Tewdwr murdered Elwysti, regaining the whole of Brycheiniog; the Church apparently forced him to donate Cwmdu to the church, as punishment for breaking his oath. Mists of time At this point, records about Brycheiniog's leadership become primarily genealogical, and certainly vague, but are unfortunately quite inconsistent with one another, and appear sometimes to be confused with genealogies of other realms. There are a number of possible conclusions: that Rhain's son Tewdwr (also known as Tewdos) had two sons, Maredudd and Nowy Hen, between whom the land was divided; Maredudd received Dyfed and Nowy Hen received Brycheiniog. In conjunction with this, that Tewdos' mother (Rhain's wife) was the daughter of Elisedd