There is some disagreement over the meaning of the Mórrígan's name. It can be straightforwardly interpreted as "great queen" (Old Irish mór, great; rígan, queen); however it often lacks the diacritic over the o in the texts. Alternatively, mor (without diacritic) may derive from an Indo-European root connoting terror or monstrousness, cognate with the Old English maere (which survives in the modern English word "nightmare") and the Scandinavian mara. This theonym appears to be derived either from Proto-Celtic *Māro-rīganījā meaning "great queenly [spirit]" or else from *Moro-rīganījā meaning "nightmarish queenly [spirit]".
There have been attempts to link the Arthurian witch, Morgan le Fay, with the Mórrígan. Morgan first appears in Geoffrey of Monmouth's Vita Merlini (The Life of Merlin) in the 12th century. However, the etymologies proposed do not seem
Her earliest appearances are in stories of the Ulster Cycle, in which she has an ambiguous relationship with the hero Cúchulainn. In Táin Bó Regamna (the Cattle Raid of Regamain), he challenges her, not realizing who she is, as she drives a heifer from his territory, and earns her enmity. She makes a series of threats, and foretells a coming battle in which he will be killed. She tells him, enigmatically, "I guard your death".
In the Táin Bó Cuailnge queen Medb of Connacht launches an invasion of Ulster to steal the bull Donn Cuailnge; the Mórrígan appears to the bull in the form of a crow and warns him to flee. Cúchulainn defends Ulster by fighting a series of single combats at fords against Medb's champions. In between combats the Mórrígan appears to him as a young girl and offers him her love, but he spurns her. In response she intervenes in his next combat, first in the form of an eel who trips him, then as a wolf who stampedes cattle across the ford, and finally as a heifer leading the stampede, just as she had threatened in their previous encounter. However Cúchulainn wounds her in each form and defeats his opponent despite her interference. Later she appears to him as an old woman bearing the same three wounds that her animal forms sustained, milking a cow. She gives Cúchulainn three drinks of milk. He blesses her with each drink, and her wounds are healed.
In one version of Cúchulainn's death-tale, as the hero rides to meet his enemies, he encounters the Mórrígan as an old woman washing his bloody armour in a ford, an omen of his death. Later in the story, mortally wounded, Cúchulainn ties himself to a standing stone with his own entrails so he can die upright, and it is only when a crow lands on his shoulder that his enemies believe he is dead.
The Mórrígan also appears in texts of the Mythological Cycle. In the 12th century pseudohistorical compilation Lebor Gabála Érenn she is listed among the Tuatha Dé Danann as one of the daughters of Ernmas, granddaughter of Nuada.
The first three daughters of Ernmas are given as Ériu, Banba and Fódla. Their names are synonyms for Ireland, and they were married to Mac Cuill, Mac Cécht and Mac Gréine, the last three Tuatha Dé Danann kings of Ireland. Associated with the land and kingship, they probably represent a triple goddess of sovereignty. Next come Ernmas's other three daughters: the Badb, Macha and the Mórrígan. A quatrain describes the three as wealthy, "springs of craftiness" and "sources of bitter fighting". The Mórrígan's name is said to be Anann, and she had three sons, Glon, Gaim and Coscar. According to Geoffrey Keating's 17th century History of Ireland, Ériu, Banba and Fódla worshipped the Badb, Macha and the Mórrígan respectively, suggesting that the two triads of goddesses may be seen as equivalent.
The Mórrígan also appears in Cath Maige Tuireadh (the Battle of Mag Tuired). She keeps a tryst with the Dagda before the battle against the Fomorians. When he meets her she is washing herself, standing with one foot on either side of a river. After they have sex, the Morrígan promises to summon the magicians of Ireland to cast spells on behalf of the Tuatha Dé, and to destroy Indech, the Fomorian king, taking from him "the blood of his heart and the kidneys of his valour". Later, we are told, she would bring two handfuls of his blood and deposit them in the same river (however, we are also told later in the text that Indech was killed by Ogma).
As battle is about to be joined, the Tuatha Dé leader, Lug, asks each what power they bring to the battle. The Mórrígan's reply is difficult to interpret, but involves pursuing, destroying and subduing. When she comes to the battlefield she chants a poem, and immediately the battle breaks and the Fomorians are driven into the sea. After the battle she chants another poem celebrating the victory and prophesying the end of the world.
In another story she lures away the bull of a woman called Odras, who follows her to the otherworld via the cave of Cruachan. When she falls asleep, the Mórrígan turns her into a pool of water.
Nature and functions
The Mórrígan is often considered a triple goddess, but her supposed triple nature is ambiguous and inconsistent. Sometimes she appears as one of three sisters, the daughters of Ernmas: the Mórrígan, the Badb and Macha. Sometimes the trinity consists of the Badb, Macha and Nemain, collectively known as the Mórrígan, or in the plural as the Mórrígna. Occasionally Fea or Anu also appear in various combinations. However the Mórrígan also frequently appears alone, and her name is sometimes used interchangeably with the Badb, with no third "aspect" mentioned.
The Mórrígan is usually interpreted as a "war goddess": W.M. Hennessey's "The Ancient Irish Goddess of War," written in 1870, was influential in establishing this interpretation. Her role often involves premonitions of a particular warrior's violent death (suggesting a link with the Banshee of later folklore).
It has also been suggested (notably by Angelique Gulermovich Epstein in her dissertation War Goddess: The Morrígan and Her Germano-Celtic Counterparts) that she was closely tied to Irish männerbund groups (described by Máire West in her article "Aspects of díberg in the tale Togail Bruidne Da Derga", Zeitschrift für Celtische Philologie vol. 49-50, p. 950 as: "...bands of youthful warrior-hunters, living on the borders of civilized society and indulging in lawless activities for a time before inheriting property and taking their places as members of settled, landed communities,") and that these groups may have been in some way dedicated to her. If true, her worship may have resembled that of Perchta groups in Germanic areas.
However, Máire Herbert has argued that "war per se is not a primary aspect of the role of the goddess", and that her association with cattle suggests her role was connected to the earth, fertility and sovereignty; she suggests that her association with war is a result of a confusion between her and the Badb. She can be interpreted as providing political or military aid or protection to the King - acting as a Goddess of Sovereignty, not necessarily a war goddess.
The Fulacht na Mór Ríoghna, the hearth or cooking pit of the Mórrígan, in County Tipperary suggests an association with the home or possibly with hunting. The Dá Chich na Morrigna or two paps of the Mórrígan, a pair of hills in County Meath, suggest a role as an earth goddess, comparable to Danu/Anu, who has her own paps in County Kerry.