Dal Riata was the name given to a kingdom established (according to some accounts) by a son of Conair Moir, a descendant of Milesius, who reigned as Ard Righ between 177 and 212 AD. Conair Moir was forty-one generations removed from Tighernmas, and ninety-six from Adam, according to the legendary genealogies.
Conair Moir had a number of sons, to whom he gave the name, Cairpre. It is believed that one of those sons was Cairpre Riata, and from him the kingdom gained its name: Dal Riata. According to legend, during Conair Moir’s reign as Ard Righ, there was a severe famine throughout the land (i.e. Munster). The three sons named Cairpre set out to search for new lands which would support their kinsmen. Cairpre Riata traveled to the north east, and there chose lands on which he and his family settled.
Of all the various Irish tribes, the Romans knew the people of Dal Riata as the Scotti, derived from their maternal ancestor, Scota. Of all the tribes which descended from Milesius and his ancestors, the Dal Riata was the most successful at retaining and spreading the Gaelic language. Perhaps that is why, of the various tribes of Scythian/Galacian origin, the Dal Riata alone has been viewed in history as the inheritors of the legacy begun by Gaodhal Glas and passed through the sons of Milesius. In an time when the history of a nation or people could only be preserved through vocal means, the importance of language was paramount.
The kingdom of Dal Riata started in the north, but was relocated twice. The people of Dal Riata moved southward from the Ulaid, which encompassed the present-day province of Ulster into the region now known as Munster, where they became involved in a war between two kingdoms already established there. They allied themselves with the Eoganachta against the Erna Mumaim, and were victorious. But they were not destined to remain there long. A famine forced the Dal Riata to moved back to the Ulaid.
The Ulaid was, by the time the Dal Riata returned, inhabited by two kingdoms: the Dal Fiatach and the Dal nAraide. The Dal nAraide is associated with the tribe known as the Cruithne (variously, Cruithneaigh) according to some historians. They are believed to have been either descended from the Picts, or closely allied with them, and journeyed from Alba, or present-day Scotland to establish a settlement in Eire.
The Picts were a ‘native’ tribe who inhabited the land that would one day be called ‘Scotland.’ It is believed that they were not a Celtic people. So little is known about the Picts that even their name for themselves is not known at the present time. Legend states that the Picts, or Cruithne, arrived at Eire during the reign of Heremon. They were seeking a place at which to settle. Heremon would not agree to their establishing a settlement in Eire, but he did give them the widows of the Tuatha de Dananns and directed them to cross the Irish Sea to establish their own settlement in Alba. It is said that because of this, the Picts were indebted to the Scythians and paid a yearly tribute to them. The name of ‘Pict’, given to the Cruithne by the Romans, comes from the Latin word, ‘Picti’ which means ‘painted ones’ or ‘tattooed warriors.’ They were one tribe which the Romans were never successful in subduing. Hadrians’ Wall was built by the Romans to prevent the Picts from venturing southward. The Pictish kingdom that emerged in the 6th Century AD was actually a combination of a number of iron-age tribes known to the Romans as the Picts, the Epidii and the Caledonii.
The Dal Riata made contact with the Picts a number of times from the 4th Century onward. Attempts may have been made to subdue the Picts, but not so much by open warfare as by peaceful assimilation. The Dal Riata men, by marrying Pictish women, attempted to inherit the kingdom by gaining a footing in the matrilinear succession of the royal Pictish line.
The Dal Riata allied themselves with the Dal nAraide in Eire, and it is believed that Cairpre Riata and a number of his kinsmen made a journey to Alba, perhaps to further cement the relationship between the two kingdoms. This was about the year 125 AD. The first mention of the Dal Riata in Alba in writing appeared in 400 AD when Roman historians noted an attack on the Roman-held Hadrian’s Wall by a combined force of Picts and their ‘Scotti’ allies. It would be apparent that contact between the two tribes had occured earlier than that date. Despite any such contact, the kingship of Dal Riata remained in Eire until some nineteen generations later. It was then that the sons of Eirc established a settlement on the west coast of Alba, in the vicinity of present-day Argyllshire. Unlike the earlier migration, the kingship was transported with them and remained thereafter in Alba, or Scotland.
Near the end of the Fifth Century AD, a figure named Eirc (variously, Erc) became the ruler of the kingdom of Dal Riata; Eirc died in 474 AD. The story of Eirc and his sons forms the basis of the oldest document known to exist regarding Dal Riata. The Senchus Fer n’ Alban (i.e. The Census Of The Men Of Alba) is believed to originally have been written during the 7th Century. That original document no longer exists; a copy was made during the 10th Century, and it is that copy that exists today. The Senchus Fer n’ Alban was part genealogical record and part inventory of the territories of the descendants of Eochaid Muin~remor:
“A statement of the history of the men of Scotland begins here.
The statement at the beginning of the Senchus that: “Others say that this Erc had another son who was called Muredoch.” would explain how the Stone of Destiny came to be in the possession of the Dal Riata and eventually taken to Scottish Dalriada by Kennth Mac Alpin. Muiredach Mac Erc is often listed in the early sources as Muiredach Mor Mac Erc, signifying that he reigned as an Ard Righ, or High King of Eire. The legends state that Fergus Mor Mac Eirc received the Stone of Destiny from his brother Muiredach, High King of Eire.
It was Eirc’s sons who carried Dal Riata across the Irish Sea to be planted in Alba. According to legend, the sons of Eirc left their homeland on Eire at the place known as the Giant’s Causeway a natural formation of basalt columns jutting into the Irish Sea, in Ireland’s present-day County Antrim. The Annals Of The Kingdom Of Ireland noted that:
"The Age of Christ, 498 recte 503. The twentieth year of Lughaidh. Fearghus Mor, son of Erc, son of Eochaidh Muinreamhair, with his brothers, went to Alba Scotland."
As can be seen in the above reference, it was generally believed that Eirc was a male, but there are certain historians who have proposed rather convincing arguments to the effect that Eirc might have been female, and a descendant of the Pictish royal line. The hereditary line of leadership in the Pict tribes descended through the female side. If that were true, then the sons of Eirc would have been descended from both the Scythians or Scots and also the Picts.
The domain of the kingdom of Dal Riada in Alba, or Scotland, was established by three sons of Eirc, Fergus Mor, Loarn and Aengus at present-day Dunadd, near the mouth of the River Add where it empties into Crinan Loch in Argyll. Three settlements were initially established on Islay, Lorn and Kintyre. The colony of which the settlements were segments, was called Ar-geal, or Argyll, meaning the ‘Eastern Irish.’ The Scottish Dalriada, as it is generally known today, would eventually be extended from present-day Argyllshire into Perthshire, then Lothian, and then into Mar and the Highlands.
The two parts of the kingdom of Dal Riata were ruled as a single unit for a period of time. But in the latter half of the 6th Century AD, certain of the land in Argyll was recaptured by the Picts. It was taken by the Scots once more in 574 by a new king of Dalriada, Aidan Mac Gabhran, a great-grandson of Fergus Mor Mac Eirc. Then, in 637 the Irish Dal Riata was destroyed with the defeat of the army of Domnall Brecc, the grandson of Aidan Mac Gabhran by the Ui Neill at the battle of Mag Rath. Increasing Norse incursions all along the coast of Ireland convinced the descendants of Heremon that there was no choice but to abandon the Irish Dal Riata. With the Dal Riata homeland lost, the Scottish Dalriada became the focus of the kingdom. The name of Dal Riata would likewise disappear with the loss of the Irish homeland. The members of the colony established on Alba would, more increasingly, be known as the Scotti or Scots.
Aidan Mac Gabhran was the first Dalriadan king to be coronated by a member of the Christian clergy. He was consecrated on the isle of Iona by St. Columba. Aidan Mac Gabhran and his wife, Ygerna Del Acqs, gave birth to eight children, the second of which was a son, born in 559, whom they named Arthur, and who became known as Arthur of Dalriada. This Arthur of Dalriada married the daughter of Leo de Grance, Gwenhwyfar de Bretagne. The two would be later known through the romanticization of actual history as King Arthur of the Round Table and his wife, Gwenivere.
Along with the sons of Eirc, Christianity spread from Eire to Alba, and it was probably because of it that the Dalriada culture was able to make a steadfast foothold in Alba and then branch out like it did. In 563 AD the monk, Colum Cille, better known as St. Columba, established a monastery on the island of Iona to both serve the Scottish Dalriada, and to convert the Picts.
The Dalriada expansion westward and northward across Alba and into the lands of the Picts continued relatively unabated until the 10th Century. Of course, there were victories and defeats for both kingdoms as the two intruded on each other. A particularly noteworthy instance occurred between 731 and 736 AD, when the Pict King Oengus I invaded and captured the fortress at Dunadd. By 756 the Scots had regained their territory. Expansion southward, though, was thwarted by the Northumbrians as early as the year 603 AD, when the Dalriadan forces under King Aidan Mac Gabhran was defeated by the Northumbrian King Aethelfrith at the battle of Degastan.