Roman Iron Age Fortriu is first recorded by the Roman author
Ammianus Marcellinus, who writing in 392 used the
Latin name
Verturiones to describe one of the two
gentes or "peoples" of the
Picts who took part in the
Great Conspiracy of 367–368. Although alongside the
Dicalydones they are clearly described as Pictish, at this time this may just have been a pejorative Roman word for
unromanised Britons. The
Verturiones were probably based like their successors around the
Moray Firth. It is not clear what relationship they had to earlier peoples documented in the same area, such as the
Vacomagi and
Decantae surveyed under
Agricola in the 1st century and listed in
Ptolemy's
Geography, but archeological discoveries at
Birnie near
Elgin indicate that Rome had remained in diplomatic contact with the area throughout the 2nd century. The
Verturiones may have emerged as part of a pattern seen in other Roman frontier zones such as Germany, where areas beyond the border saw population groups amalgamating into fewer but larger political units. As well as the two Pictish groupings, the conspiracy of 367–368 included
Scotti from
Ireland;
Attacotti whose origins are uncertain but likely to have been somewhere within the
British Isles; and
Franks and
Saxons from across the
North Sea; suggesting high levels of intercommunication between the
Verturiones and the peoples of Ireland and continental Europe. The conspiracy may have been caused by a decline in the level of subsidies given to barbarian tribes by the emperor
Valentinian. The fact that
Fullofaudes, the leader of the northern Roman troops, was captured rather than killed suggests that the Pictish invaders may have been motivated mainly by extracting treasure.
Verturian hegemony After the 4th century Fortriu is not explicitly mentioned in documentary sources until 664, but there are indications that Fortriu's later power may have been foreshadowed in the late 6th century.
Adomnan's
Life of Columba describes the stronghold of the Pictish king
Bridei son of Maelchon, who ruled from 554 to 584, as being by the
River Ness, in or near to the heartland of Fortriu. Bridei is depicted by Adomnan as overlord of a
regulus or "underking" of
Orkney, and was separately described by the
Northumbrian historian
Bede as
rex potentissimus or "very powerful king". Irish annals record a "flight" or "migration" of Gaels "before the son of Mailcon" between 558 and 560, suggesting that by then Bridei's power may have been extending into the territory of
Cenél Loairn in
Dál Riata, at the opposite end of the
Great Glen from Fortriu, and Adomnan records a slave girl from Dál Riata at Bridei's court at the time of Columba's visit. By the end of the 7th century Fortriu had established a dominant position over most or all of the Picts, one of the most significant developments in the history of early medieval Scotland, described by historians as the
Verturian Hegemony. The status of Fortriu as a powerful over-kingdom can be seen from the reign of
Bridei son of Beli, who was the first king to be explicitly described as "King of Fortriu" in contemporary chronicles, and whose victory over
Ecgfrith of Northumbria at the
Battle of Dun Nechtain in 685 extended Fortriu's power southward, replacing Northumbrian rule north of the
Forth. Bridei had possibly been a sub-king of the Northumbrians at the start of his reign in 671, but began to extend his power with a siege of
Dunottar in 680 and an attack on
Orkney in 681. As the influence of the kings of Fortriu grew they promoted the idea of the Picts as a single people with a single king, playing a key role in uniting the Picts and establishing a self-conscious Pictish identity. The continuing power of the kings of Fortriu over the Picts can be seen in the activities of Bridei son of Beli's successors.
Bridei son of Derilei and the cleric
Curetán of
Rosemarkie were the only Pictish signatories to
Cáin Adomnáin or "Law of the Innocents" in 697, indicating that Bridei was able to enforce adherence of the Picts as a whole; while
Nechtan son of Derilei's church reforms of the 710s were described by Bede as being enacted "throughout all the provinces of the Picts". The kings of Fortriu maintained their control over southern Pictish territories in the 7th and 8th centuries by planting them with loyal Gaelic lords and their military retinues; creating
provinces named after leading Gaelic kindreds including
Cenél Comgaill in
Strathearn,
Cenél nÓengusa in
Angus and
Cenél nGabráin in
Gowrie. A series of campaigns under
Onuist son of Uurguist between 731 and 741 saw this power extended further with the invasion and conquest of the
Gaelic kingdom of
Dál Riata, located in the area of modern-day
Argyll. Onuist became the first Pictish king known to have invaded
Northumbria and
Strathclyde and may even have invaded
Ireland, establishing a domination over northern Britain unmatched by any preceding king, that would not be rivalled again for another 150 years. A period of instability in Fortriu following the death of
Elphin son of Wrad in 780 saw four rulers in quick succession – three from the family of Onuist son of Uurguist – and allowed Dál Riata to reassert its independence. The succession of
Constantín son of Uurguist to the kingship of Fortriu in 789 was challenged by the Dál Riatan king
Conall mac Taidg, but Constantín proved to be strong leader and reigned through to his death in 820.
The Viking Age The dominance of Fortriu and the
House of Uurguist, which had lasted for over fifty years and for much of that period had also extended to Gaelic
Dál Riata and the Britons of
Strathclyde, came to a sudden and dramatic end with a decisive defeat by
Vikings in the
Battle of 839. The
Annals of Ulster record the deaths in the battle of the king of Fortriu,
Wen son of Onuist, and his brother
Bran son of Onuist, together with the king of Dál Riata
Áed mac Boanta – suggesting Dál Riata was still under Pictish control – alongside "others almost innumerable". The fact that so many were slain, including the kings of both Fortriu and Dál Riata, suggests that Wen had had time to gather his forces, and that this was the culmination of a campaign rather than a fortuitous raid. This was one of the most important and decisive battles in British history and although its location is uncertain it probably took place in the heartland of Fortriu on the shores of the Moray Firth. The Viking Kings of Dublin
Amlaíb and
Auisle are recorded in the
Annals of Ulster going to Fortriu and plundering "the entire Pictish nation" in 866. Although the chronology of written sources is confused, they probably occupied Fortriu for three years and took hostages, before
attacking Dumbarton Rock in 870 and returning to Dublin in 871, bringing with them "a great prey of English, and Britons and Picts."
Fragmentation and disappearance Fortriu continued to be recorded into the early 10th century, suggesting a degree of continuity with the earlier period of over-kingship. The
Annals of Ulster record the "men of Fortriu" killing the Scandinavian leader
Ímar ua Ímair in 904, four years after it had started using the description
ri Alban for the
King of Alba. The last dated reference to Fortriu in any of the
Irish Annals is for 918 in the
Fragmentary Annals of Ireland, where the phrases "Men of Fortriu" and "Men of Alba" are treated as synonymous. The
Historia Regum Anglorum describes King
Aethelstan of England wasting
Scotia as far as Dunottar and
Wertermorum – the "muir of Fortriu" – in 934, indicating that Fortriu was still recognised at this stage as a reference for features in the landscape. The complete disappearance of the name Fortriu beyond this point suggests that it fragmented into its successor polities – the
provinces of
Moray and
Ross – during the 10th century. Moray is first recorded in an entry in the
Chronicle of the Kings of Alba for the reign of
Malcolm I, which lasted from 943 to 954; while Ross first appears in the documentary record in a
hagiography of the Scottish-born saint
Cathróe of Metz, written in
Metz between 971 and 976. ==Location==