He dies of disease suddenly.
The later chronicles differ as to the place of his death. By some he is said to have died at Rath Inveramon, and by others to have been slain at Scone. These names, however, can all be referred to localities in the immediate neighbourhood of Scone, and probably belonged to the defences and possessions of that central seat of the monarchy.[[456]] The only event recorded in his reign is the curious notice in the Pictish Chronicle that in his time the Gaedhel established with their king in Forteviot the rights and laws of the kingdom of Edus, son of Echdach.[[457]] The reference is here unquestionably to that Aedfin, son of Eachach, whose death as king of the Dalriads is recorded by the Annals of Ulster in 778, and who appears to have been the last of the Scots who attempted to make any stand against the rule of the Picts over Dalriada, and by his kingdom that of the Scots of Dalriada must be meant. Among the rights and laws now established was probably the law of succession among the Scots, which is usually termed the law of Tanistry, and which, in its preference of the male over the female succession, was opposed to that of the Picts. This law, as we have seen, had to some extent been partially introduced among the southern Picts before the accession of Kenneth, and would therefore now be established at Forteviot with less difficulty.
A.D. 863.
Constantin mac Kenneth, king of the Picts.
It was in accordance with this law that Donald was succeeded by Constantin, son of Kenneth mac Alpin, who reigned sixteen years. The Pictish Chronicle records that in his first year Maelsechnaill, king of Ireland, died, and his death took place on Tuesday the 30th November 863,[[458]] which gives us the true commencement of this reign. After two years Amlaibh with his Gentiles laid waste Pictavia, and occupied it from the kalends of January to the feast of St. Patrick—that is, from the first of January to the 17th of March; and in the following year, while withdrawing with his booty, he was attacked and slain by Constantin.[[459]]
The Ulster Annals record the same event when they tell us that in 866 Amlaiph and Aiusle went to Fortrenn with the Galls of Erin and Alban, and laid waste all Cruithintuaith, of which name Pictavia is here the Latin equivalent, and took hostages.[[460]] This Amlaib, or Amlaiph, was Olaf the White, king of Dublin, who had married a daughter of Kenneth mac Alpin; and his occupation of the country and the hostages he took may have been in connection with some claim through his wife; but his death did not really take place till some years after,[[461]] for we find from the Ulster Annals that in the year 870 Alclyde was besieged by the Northmen under the same Amlaiph, along with Imhair, another of their kings, and destroyed after a four months’ siege. Another annalist tells us that after having wasted the people who were in the citadel by hunger and thirst, and succeeded in drawing off the water from the well that was in it, the Northmen entered upon them and first carried off all the riches that were within it, and afterwards a great host of prisoners were brought into captivity.[[462]] On this occasion they appear to have also attacked both the Picts of Galloway and the Angles of Bernicia, for in the following year we are told that Amlaiph and Imhair returned to Dublin from Alban with two hundred ships, and a great booty of men, Angles, Britons, and Picts, was brought with them to Ireland in captivity.[[463]] After this we hear no more of Amlaiph or Olaf the White of Dublin. In 872 the Ulster Annals tell us that Artgha, king of the Britons of Strathclyde, was slain by the advice of Constantin.[[464]] This was Arthgal, a lineal descendant of Dunnagual, whose death was recorded in 760, and the father of that Run who married the daughter of Kenneth mac Alpin.[[465]] We thus see that after the death of the last of this line, who is called king of Alclyde, in 750, and the subjection of his kingdom to the Angles, it now again reappears as an independent kingdom with the new designation of that of the Britons of Strathclyde. It was probably in connection with this event that St. Berchan, in referring to the battles fought by Constantin, says—
The hazard through which three battles are gained
Against the Gentiles of pure colour (the Fingall).
The fourth battle, the battle of Luaire,
Against the king of the Britons of green standard.[[466]]
Luaire is probably Carlowrie in West Lothian.