Cunedda dynasty ended, Merfynion began

The extinction of Cunedda's lineal (direct descendant) male line inheritance of the Kingdom of Gwynedd. The emergence of the Merfynion dynasty from the House of Manaw in the 9th century, and the beginnings of the Cambro-Norse era (Wikipedia articles linked).

The Kingdom of Gwynedd had firmly established itself as a contender for supremacy as ruler of the British Isles after the Roman occupation of Britain at the end of the 4th century. Then came the Anglo-Saxon invasions between the 5th to 11th centuries. This was the prequel to and at the same time as the Cambro-Norse era against the Vikings, lasting between the 850s to the 1100s, culminating in the Norman invasion. The consecutive invasions of Wales meant a need for a change in personnel to protect the Kingdom, this forced the emergence of the Merfynion dynasty, named after a 9th century King of Gwynedd, Merfyn Frych (Merfyn the Freckled, Old Welsh: Mermin, Merfyn the oppressor).

Image courtesy of Wikimedia Commons, attributed to Notuncurious, Kingdom of Gwynedd under Merfyn Frych, circa. 830.

Cambro-Norse people were involved in a tumultuous time for the Welsh Kingdoms, especially Gwynedd, resulting from the Viking invasion and subsequent raids. The era in Wales coincided with internal strife for the Kingdom. That was after the direct male line lineal inheritance of the Kings of Gwynedd had ended, this was after centuries of the custom of the Kingdom being inherited from father to son, a tradition that went back to 1,000 BC, and the Kings of Britain. Specifically, it was Merfyn Frych who had assumed the throne of Gwynedd as a King from 825 to 844 and was also recorded as King of the Britons in 829. That was after battles against the medieval Kingdom of Mercia, and the invading Saxons. He was not a direct male descendant of the founder of the Kingdom, Cunedda, but a female line descendant, the first of such to become the King of Gwynedd. His grandfather (mother's father) was Cynan Dindaethwy. Cynan was the first to be named King of Wales and he held his court at the east of Anglesey named Llys Dindaethwy, he was killed at his court in the battle of Llanfaes against his brother and rival, Hywel ap Caradog, c. 816 (battle debated about veracity). Rhodri Molwynnog (Rhodri the Bald and Grey, d. 754), their father (Cynan's stepfather) was the King of Gwynedd, King of the Britons as a descendant of Cadwaladr, the traditional final King of Britain from a century before his ascension. Rhodri was recorded as having battled the English in Cornwall, in 721 AD. The period running up to Merfyn's ascension was deemed unlucky, with bovine plague (mad cow disease) killing cattle, and Llys Dindaethwy being struck by lightning. The Llys is traditionally the location of a prehistoric settlement that culminated in a Bronze Age hillfort, and later on, the Iron Age settlement today known as Arthur's Table (Bwrdd Arthur in Welsh), or Din Sylwy. 

Wikimedia Commons, attributed to Jason.nlw, wall of Arthur's table, Anglesey.

Mentioning the name Arthur, it is said that King Arthur's sibling, and Uther Pendragon's son, Madoc, was the first to leave Britain for America in 562 AD, a millennium before Columbus sailed from Spain, and over 500 years before Madog ap Owain Gwynedd from Wales, those were troubling times following the Saxon invasion of the British shores. However, almost nothing has been recorded in history about Madoc's journey, it's pretty much a commercial secret today, leaving most to question the claim. A prime example is the confusion about artwork in St. Andrew's Church in Stoke Dry, Rutland, England, as there's a wall painted mural supposedly depicting St. Edmund and Vikings c. 869, or potentially King Arthur and native Americans, circa the 6th century.

Returning to the Kings of Gwynedd, Merfyn's mother was Ethyllt daughter (ferch in Welsh) of Cynan, she became mother to a King of Gwynedd as an heiress to the Kingdom. However, Gwynedd was a Kingdom ruled by Kings only, and it was during this time that the ruler was a male-orientated role, and the names of Queens were vaguely and rarely mentioned in the historical records. The Welsh outlook was that a stranger had taken the throne of Gwynedd. Frych's father was Gwriad ap Elidyr, chief of the Manx people as the King of Mann, from the Isle of Man. The small island is north of Wales and south of Scotland near England in the Irish Sea. Frych's father's background gave him the support of a foreign court in Gwynedd. As well as fact his father was from outside of Gwynedd, which was the first time for a King of Gwynedd, but, his wife Nest was of the line of the King of Powys, making the first merger between the main Welsh royal houses for Gwynedd. Merfyn became King and inherited the King's royal estates of Anglesey and Gwynedd from his great-uncle, Hywel. But not just Gwynedd, he was also named King of Wales after his grandfather Cynan (Conan in English), who was the first to hold the title of King of the modern territory known as Wales (Cymru in Welsh). However, it wasn't until the 10th century that the Welsh name Cymru was first recorded in its current name form, originally as Kymry, thus replacing its name as Cambria. 

The new era involved skirmishes with Vikings for the first time, and saw Wales descend into chaos not just internally as a family dispute over the crown, but now also due to war from both sides of the country. To the east was the English Kingdom of Mercia which has already subjugated Wales with the aid of the Saxons. To the west emerged the Scandinavian (Swedish and Norweigan) Vikings who aligned themselves with the Irish Kingdom of Dublin. The Kings would become warlords battling against their neighbours to protect their kin. By 817, Coenwulf of Mercia took full advantage of Gwynedd's internal weaknesses and invaded Wales, he successfully kept the Welsh under control through warfare, as did his son. The Snowdonia area of Wales was devastated by raids several times for basically a decade. The war between the allies of Gwynedd and Powys against Mercia would continue for decades to come and would see a King perish in battle before Gwynedd would regain its power against the Saxons. Erstwhile defending themselves against first the Vikings and then eventually the French Normans, who were descendants of a Viking ruler.

Wikimedia Commons, attributed to Malost, Gaut's Cross at Kirk Michael, Isle of Man.

The Welsh called the 9th to 10th centuries in Gwynedd the era of the Merfynion, a second royal family dynasty of Wales after Cunedda, the founder of Gwynedd's royal family. Merfyn's royal house is also recognised as the House of Manaw, as the location of his father's side of the family. There had been confusion amongst historians about the true location of Manaw, there are two potential locations. Firstly Manaw Gododdin in southern Scotland or northern England, the location Cunedda emerged from in the 5th century, or Manaw, aka the Isle of Man (Ynys Manaw, Welsh for island). Perhaps it was the same families who were migrating often between two places which are either side of Great Britain. However, it has been noted through archeological excavations that the presence of Christian Celts on the Isle of Man does date to the 9th century, but there were also Norse settlements on the island by then. For instance, there is a Viking settlement in an area named Balladoole, where a ship burial was discovered. The presence of Vikings makes us believe that perhaps the King of Mann fled his Kingdom to a neighbouring ally due to the threat of the foreign invading force. The Isle of Man would later be incorporated into the Norse Kingdom of the Isles, this era of Viking expansion was known as the 'Dyflinnarskiri' (Dyflin; Dublin?), and it involved the Anglo-Danes and northern Scandinavian Vikings separately vying for their own ruling Kingdoms in the British Isles. Also, another clue about the whereabouts of Manaw is the similarity between Celtic crosses of that era. These religious symbols, like sculptures, were all very similar in design and then erected in areas of Dublin and the Isle of Man, and also Edren (Edern) in Gwynedd, Wales. These virtually identical religious symbols confirm the movement of the same people between those three countries. On Man was discovered Celtic Cross in Latin writing stating: "Crux Guriat" (Gwriad's cross), carbon dating to the 9th century, which fits perfectly into Merfyn's timeline. This is a definitive point of interest to make a final conclusion in determining the whereabouts of a man named Gwriad, the name of Merfyn's father.

The presence of the Welsh in and around the Irish Sea would later be confirmed by Gruffudd ap Cynan of the House of Aberffraw. He was raised in a Gael-Norse (Irish Viking) family in Dublin in the 11th century before becoming the King of Gwynedd. Therefore, it is very plausible that Merfyn Frych was part Manx from another part of the Irish Sea other than Gwynedd, and this can be observed by the Celtic Christian religion spreading around coastal areas north and west of Gwynedd and Anglesey with the assistance of the Scandinavian Vikings, many of whom had converted to Christianity and started sculpting their own crosses. By the 9th century, the Church of Wales had already been established for over three centuries. The Welsh were and still are traditionally religious Christians. Frych's family, the Kings established Christian places of worship and monasteries throughout Wales. Frych's father's ancestors were Kings from outside of Wales, a tradition that would repeat itself in the centuries following Gruffudd's ascension as King. Gwynedd and Wales did not have a foreigner in power since Cunedda, four centuries before Merfyn. In the early medieval ages, only Welshmen were rulers of Gwynedd and Wales from after the Roman period. The Merfynion dynasty would signal the mid-way stage of the Kingdom of Gwynedd and pave the way for the final flurry of Kings from Gwynedd in Wales, and this next time, the Kingdom would separate from the position as Kings of Britons. Instead, the Merfynion would emerge as rulers and Kings of Wales for the first time and the final time as Kings of the Britons.