In 367 AD all of Britain's barbarian enemies - the Irish, Saxons, Franks, and Picts, launched a series of raids and attacks all along the borders.
The history of Roman Britain is filled with various raids from the barbarian tribes that lived just beyond the Roman borders. The Picts attacked from Scotland, the Irish raided Wales, and the Saxons and Franks struck from across the channel. Barbarian raids were a part of life for the Brits who lived along the borders and coastline, but they were never a threat to the overall stability of Roman Britain. This changed in 367 AD.
According to Irish tradition, around this time, the High King of Ireland married a Saxon wife who would become mother to the famous Niall of the Nine Hostages. Part of the arrangement of this marriage was that the Saxons (and possibly allied Frankish tribes) would launch a diversionary attack against the southeast of Britain; meanwhile the Irish and the Picts would attack from the north and the west.
It is hard to judge the true size and impact of the attacks of 367. There is only one source, and it is possibly biased, yet some facts can be taken at face value. At least two men of high standing were killed in the attacks: Nectaridus, Count of the Costal Defence, and General Fullofaudes. Also, the attacks were of such a magnitude that Emperor Valentinian despatched one of his trusted agents, Count Theodosius with a body of highly experienced men.
Upon arriving in Britain, Theodosius quickly set the south in order and marched north where the threat was much greater. With his superior forces, Theodosius was easily able to round up and defeated the scattered forces of the enemy and temporarily restore security to Britain. However, it was his plan to keep the peace that would have the longest impact. Theodosius discovered that the men in charge of the network of forts that ran along the length of Hardian’s Wall had become corrupt and were working with the enemy. Theodosius dismantled these defences and replaced it with a new system whereby he installed Roman leaders as rulers over the border tribes that submitted to his army. Four men in particular are known to have taken up these positions. Quintilius Clemens, who came from the Mediterranean, ruled over the Clyde. Paternus from Kent and Catellius Decianus were put in charge of parts of the Votadini tribe on the northeast coast. Finally, Donatus ruled in the southwest of Scotland.
Several years after his arrival, Theodosius had restored the peace in Britain, and the Emperor ordered him to northern Africa to counter a similar problem. There Theodosius was killed in 375 AD. Of the men whom Theodosius had left in charge of the Barbarian tribes, all would become hereditary kings over their tribes. The longest running of these dynasties would come from Paternus whose rule passed into Wales and would carry through the generations until finally being extinguished in the thirteenth century with the death of Llewellyn the Great.
