Supernatural features in Diarmait's reign are not limited to prose and verse works or to lives of saints. Even the
Irish annals include a reference to
druid fences being created at the battle of Cúl Dreimne. The main subject for later writers and poets however, was not Diarmait's life but his death. Diarmait is told by
Bec mac Dé that
Áed Dub, Diarmait's foster-son, will be his killer. Accordingly, Diarmait banishes Áed Dub.
Saint Ruadán gives the prophecy that Diarmait will be killed by the roof-beam of his hall at Tara. Diarmait has the beam cast into the sea. Diarmait then asks his druids to find the manner of his death, and they foretell that he will die a
threefold death, by slaughter, drowning and burning (or again: "by iron, water and fire"), and that the signs of his death will be a shirt grown from a single seed of flax, a mantle made of wool from a single sheep, ale brewed from one seed of corn, and bacon from a sow which has never farrowed. On a circuit of Ireland, Diarmait comes to the hall of Banbán at Ráith Bec, and there the fate of which he was warned comes to pass. Diarmuid dies a triple death: the roof beam of Tara has been recovered from the sea by Banbán and set in his hall, the shirt and mantle and ale and bacon are duly produced for Diarmait. Diarmait goes to leave Banbán's hall, but Áed Dub, waiting at the door, strikes him down and sets fire to the hall. Diarmait crawls into an ale vat to escape the flames and is duly killed by the falling roof beam. Thus, all the prophecies are fulfilled. When the king sent men to arrest Aedh, St. Ronan hid him and so Diarmuid had Ronan arrested and tried in his stead. He was condemned by the ecclasiastics for this act and Ronan himself uttered the famous curse, 'Desolate be Tara forever!' Soon after, Tara was abandoned, never to achieve its former splendor... [Diarmuid's wife] had an affair with Flann, so Diarmuid had Flann's fortress burnt over his head. Sorely wounded, Flann tried to escape the flames by crawling into a vat of water where he drowned... Bec Mac De [Diarmuid's druid councilor] prophesied that Diarmuid would be killed by Flann's kinsman, Aedh Dubh in the house of Banban... The manner of his death would be by slaughter, by burning, by drowning and by the ridge pole of a roof falling on his head... The Prophecy seemed so unlikely that Diarmuid scorned it, even when Banban invited him to a feast... Aedh Dubh was there and stabbed the
High King with his spear. Wounded, Diarmuid fled back into the house. Aedh Dubh's men set fire to it. Seeking to escape the flame, Diarmuid scrambled into a vat of ale. A burning ridge pole fell on to his head. The prophecy was fulfilled (Ellis, 84). Both of the elements which Evans discusses are present in this story of Diarmuid's death. In this story, there is a prophecy of the threefold death before it occurs. In fact, Diarmuid's death is foretold by three different men in the original story. Diarmuid has also clearly violated two of the three functions. He sins against the sanctity of the priestly function, by trying
St. Ronan. For this crime Ronan curses the throne at
Tara. Diarmuid also murders Flann, a violation of the warrior function. Diarmuid is punished for his transgressions by the triple nature of his death. Like tales are told of Muirchertach mac Ercae and Adomnán records that Columba prophesied a similar death, by wounding, falling and drowning, for Áed Dub. There are a number of stories in Celtic mythology that clearly are formed by the Tripartite functions of Proto-Indo-European. The theme of triple-death occurs in several places in medieval Celtic sources. The Tripartite death of Aedh is linked with another story of triple-death, which comes from the
Life of St. Columba (
Vita Columbae): Aedh, surnamed the Black, descended of a royal family, and a
Cruthinian by race. Aedh wore the clerical habit, and came with the purpose of residing with him in the monastery for some years. Now this
Aedh the Black had been a very bloodthirsty man, and cruelly murdered many persons, amongst others Diarmuid, son of Cerbul, by divine appointment king of all. This same Aedh, then, after spending some time in his retirement, was irregularly ordained priest by a bishop invited for the purpose... The bishop, however, would not venture to lay a hand upon his head unless Findchan, who was greatly attached to Aedh in a carnal way, should first place his right hand on his head as a mark of approval. When such an ordination afterwards became known to the saint, he was deeply grieved, and in consequence forthwith pronounced this fearful sentence on the ill-fated Findchan and Aedh... And Aedh, thus irregularly ordained, shall return as a dog to his vomit, and be again a bloody murderer, until at length, pierced in the neck with a spear, he shall fall from a tree into the water and be drowned... But Aedh the Black, a priest only in name, betaking himself again to his former evil doings, and being treacherously wounded with a spear, fell from the prow of a boat into a lake and was drowned. This story of triple-death corresponds to the elements which Evans finds in a whole host of similar stories. In all of these stories, the tripartite death is foretold. Here St. Columba foretells the triple death of Aedh. At the same time Columba's prophecy is a curse or a punishment which he dispenses to Aedh because of his sins. This leads to the next element common in many 'Triple-death' stories, the sins of the warrior. According to Dumezil, the warrior often commits a sin against each one of the functions. He is punished for each sin, with a punishment fitting for his crime. In this passage from the
Life of St. Columba, three specific sins are mentioned. Aedh
blasphemes by being ordained a priest outside of the
Church. This is a sin against the priestly function of Indo-European society. Aedh's second sin is murder; he has killed numerous people, most notably King Diarmuid. This is a sin against the warrior function. Aedh's last sin is against the productive/fertile function in Indo-European society, he has slept with another man—an act which is by its very nature unfertile. This is again the mythic three-fold death, and probably signifies that there was some manner of traditional account of Áed Dub. From Adomnán's account it can be surmised that Áed was deposed, or abdicated, and spent time in
Britain in a
monastery before, presumably, returning to Ulster to try to regain his throne. The report of Áed Dub's death in the
Annals of Ulster for 588 — the Annals of Tigernach place it in 579 — may contain some traces of this as it reports the killing of Áed aboard a ship. This is thought to have taken place on
Lough Neagh. ==Descendants==