There are many different ways to become god of the dead. You can win the job by chance (Hades/ Pluto), you can be cast into the underworld by other gods (Hel), marry into the job (Nergal), or you can be the first person to die.
Donn was one of the invaders known as the Milesians, after their father Mil. He was the warlike one, while his brother Armaigen was the poet/judge. They eventually did take Ireland, but not easily, and Donn never got to enjoy their victory.
Dying for the Job
There are two stories about how Donn came to die, and why his resting-place is an island off the west coast. The first comes from the Metrical Dindshenchas:
1] Tech Duinn, whence the name? Not hard to say. When the sons of Mil came from the west to Erin, their druid said to them, ‘If one of you climbs the mast’, said he, ‘and chants incantations against the Tuatha De, before they can do so, the battle will be broken against them, and their land will be ours; and he that casts the spell will die.’ They cast lots among themselves, and the lot falls on Donn to climb the mast. So was it done: Donn climbed the mast, and chanted incantations against the Tuatha De, and then came down. And he said: ‘I swear by the gods’, quoth he, ‘that now ye will not be granted right nor justice.’ The Tuatha De also chanted incantations against the sons of Mil in answer from the land. Then after they had cursed Donn, there came forthwith an ague into the ship. Said Amairgen: ‘Donn will die’, said he, ‘and it were not lucky for us to keep his body, lest we catch the disease. For if Donn be brought ashore, the disease will remain in Erin for ever.’ Said Donn: ‘Let my body be carried to one of the islands’, said he, ‘and my people will lay a blessing on me for ever.’ Then through the incantations of the druids a storm came upon them, and the ship wherein Donn was foundered. ‘Let his body be carried to yonder high rock’, says Amairgen: ‘his folk shall come to this spot.’ So hence it is called Tech Duinn: and for this cause, according to the heathen, the souls of sinners visit Tech Duinn before they go to hell, and give their blessing, ere they go, to the soul of Donn. But as for the righteous soul of a penitent, it beholds the place from afar, and is not borne astray. Such, at least, is the belief of the heathen. Hence Tech Duinn is so called.
The other story comes from the Lebor Gabala, or Book of Invasions, a pseudo-historical account of how Ireland was settled. This time, crafty Amairgen wins over the goddesses Eriu, Fotla and Banba by telling each one that he’ll name the land after them, but the warlike Donn prefers to trust to his sword, and considers parleying with the women a disgrace (81).
Then a storm whipped up by magic drives the Milesians out to sea. However, Amairgen is able to calm the waves, so that the invaders can reach Ireland.
§82. Said Donn: I shall now, said he, put under the edge of spear and sword all that are in Ireland. And the wind rose against the ship wherein were Donn and Airech, two sons of Mil, and the ship wherein were Bres, Búas, and Buaighne; so that they were drowned at the Sandhills at Tech Duinn. The grave-mound of each man is there. And there, as some say, Díl, wife of Donn, was drowned. She was a daughter of Míl, and Érimón himself laid a sod upon her. This is a sod over Díl, said he. Unde Fotla nominatur, ut quidam putant.
(The last bit reads: “Here Fotla is mentioned, as some think.”) Erimon was brother to Donn and Amairgen, and along with the fourth brother, Find Eber, became king of Ireland. More on the two kings in a post on Find. As Amairgen and the others come ashore, the poet chants the famous verse The Song of Amairgen.
Later, he would celebrate his brothers in another verse, the Cauldron of Poetry:
I being white-kneed, blue-shanked, grey-bearded Amairgen,
let the work of my goriath in similes and comparisons be related
– since God does not provide equally for all,
inclined, upside-down (or) upright –
no knowledge, partial knowledge (or) full knowledge,
in order to compose poetry for Eber and Donn with many chantings…
Going West: Tech Duinn
Donn was drowned in Kenbare Bay in Kerry (then called Inber Scene), and was buried on a tiny rock island off the main island of Dursey. It is now called Bull Rock, but to the medieval Irish it was Tech Duinn, home of the dead and their god. (The image at the top is of Bull Rock.)
His cairn was raised, and the stone of his kindred, above the broad sea: an ancient dwelling, a house of the waves, which is called the House of Donn.
This was his mighty legacy to his abundant descendants: ‘To me, to my house, let them all come after their deaths.’
– by the poet Mael Muru Othna (d. 887).
The idea that a person went to Donn after death, and that he lived at Bull Rock or Tech Duinn had a remarkably long life. Folklore collectors recorded instances right up to the middle of the last century, including one rather remarkable one, in which a dying man tells the priest he “would be up there soon, on the whaleback ‘Black Hill’, east of the cone where Donn was supposed to marshal his men…” (Müller-Lisowski: 143)
Maybe he was there all along…
While the Book of Invasions tries to give Donn a historical background, and indeed puts him rather late in the historical scheme it lays out, it seems likely that he was god of the dead all along. The name Donn now means “dark brown” but earlier meanings included “black, dark, dusky”, and is cognate to a rare Welsh word dwnn. Carey thinks Donn is “the Hidden One” (325).
The historical accounts seem to point a contrast between the soldier Donn and his brother, the poet/judge Amairgen, but the Milesians also offer us more to think about. Two of Donn’s brothers go on to be kings of Ireland, halving it between them. Because of this, it became proverbial to say that the Irish were the sons of Find Eber and Eremon. (MacKillop: 166)
Find is the Irish equivalent to the Welsh word gwyn, meaning bright. Since the Book of Invasions refers to Donn as Eber Donn, you could see a deliberate contrast between the bright Find Eber who begins a dynasty, and the gloomy Donn on his rock with the dead for company. (Including his own family; he has no surviving descendants.) (O hOgain: 166)
Donn, the Dagda and Dis Pater
This seems to put a bit of a damper on the idea that Donn might be a god like Dis Pater, whom Julius Caesar said was the ancestor of all the Gauls. However, Donn is still part of the family that all the Irish descend from, and we know that we’re all going to him. You could look on him, like Hades, as a rather gloomy uncle.
Continuing on with this idea, in a 12th-century called the Wooing of Treblann, Donn is called the foster-son of Eochaid Ollathair. This is another name for the Irish chief god, the Dagda, the Ollathair part meaning Great Father. Another source calls Donn the Dagda of Munster, which suggests that the two may be closer than we think. (Zeidler: 11-2) The Dagda would be a good candidate for an Irish Zeus, and if the two gods overlapped, they would make a good Dis Pater.
Those who favour an Indo-European explanation for the Donn/Amairgen myth see them as similar to the Indian Yama and Manu. In that myth Manu, the law-giver, sacrifices Yama, who then becomes the first being to die and so lord of the dead. (Carey, Lincoln)
Folklore and Legends
A lot of fairy lore attached itself to Donn as time went on, much of it to do with local places and customs. He took people in Clare to his home in the hill Knockfierna, and was known locally as Donn Firinne. There are many legends about him riding his horse through the sky at night, sometimes bringing bad weather in his wake.
Because of his horse-riding, he attracted a variant on the blacksmith legend, in which he took off the horse’s leg and handed it to the terrified smith to shoe for him. He went on to say that he had to fight a battle that night against another army. O hOgain (166) points out that a similar legend about Odin may be the source of this, since the Vikings did settle in Limerick. (He also resembles the Welsh Gwyn ap Nudd here; both fearsome warriors who keep the souls of the dead in their care.)
He was also known in Co. Clare as Donn Duimhche (of the Dunes), and his host supposedly used to drive off the farmers’ cattle there. He also was blamed for shipwrecks and drownings in the area. Tech Duinn in Kerry already had this reputation, and presumably any treacherous shore could take on the same resonances. (O hOgain: 166-7)
While some of these legends are similar to other fairy lore, it is clear that most of them can be related back to Donn as god of the dead and fierce warrior.
Breatnach, Liam 1981: “The Cauldron of Poesy”, Eriu 32 (1981): 45-93. (JSTOR)
Carey, John 2010: “Donn, Amairgen, Íth and the Prehistory of Irish Prehistory”: Journal of Indo-European Studies 38/3-4 (Fall/Winter 2010): 319-41. (pdf here)
Ellis, Peter Beresford 1991: A Dictionary of Irish Mythology, OUP.
MacKillop, James 2004: An Oxford Dictionary of Celtic Mythology, OUP.
Müller-Lisowski, Käte 1948: “Contributions to a Study in Irish Folklore: Traditions About Donn”, Béaloideas 1/2: 142-99. (JSTOR)
O hOgain, Daithi 1991: Myth, Legend and Romance: An Encyclopedia of Irish Folk Tradition, MacMillan.
Zeidler, J. “Ancient and Medieval Celtic Myths of Origin”, 17th Irish Conference of Medievalists: 1-19. (pdf here)