Battle of Mag Tuired

Cethlenn is unmentioned in the narrative Cath Maige Tuired, as she is not listed in the roster of Fomorians compiled by Whitley Stokes .^{[13][lower-alpha 2]}

But in this Battle of Mag Tuired (The Second Battle of Moytura), Cethlenn hurled a javelin (gae) at the Dagda giving him a mortal wound, as recorded in theLebor Gabála Érenn.^[14] It took 120 years before the Dagda died of the wound.^{[15][lower-alpha 3]}

The recounting of Cethlenn injuring the Dagda is repeated in the Annals of the Four Masters,^[16] Keating's History,^[17] and O'Flaherty's Ogygia.^[3]

Cethlenn presumably fell in battle, or so it has been commented on by John O'Mahony without clarification of source.^[18]

Enniskillen

Some local historians in the 20th century and after refer to a legend that the Cethlenn was injured and swam to Enniskillen on Loch Erne, Co. Fermanagh, where she died.^[19][20] The suggestion that Enniskillen is eponymous after Cethlenn is made in the early 17th century Annals of Clonmacnoise, though nothing about her swimming there is remarked on by 19th century writers.^[21][22] The present-day town is still situated on a river island. The town centre can only be accessed by crossing a bridge from the surrounding mainland. The town was the location of an island fortress on the River Erne once maintained by the Maguire of Fermanagh and the castle river gate entrance still stands. clan.^[22] According to local lore, the town has taken the name of a smaller island, Inis Cethen, located just south of today's East Bridge. It was long ago foretold that if the island was flooded by Erne waters, the town would fall to its enemies. Just before the Flight of the Earls (the old Gaelic rulers) this island did flood and the town of Enniskillen fell to the English. In the nineteenth century the Enniskillen borough took care to prevent the town ever being taken by an enemy again, by filling in the narrow waterway between the smaller island and the mainland. At the same time, the island's elevation was raised to the level of the mainland with earth filling enclosed inside a stone wall. This piece of ground can still be seen, home now to a stand of mature chestnut trees that overhang the river. Inis Cethlen is still enclosed by the stone wall that has prevented it flooding for the past two centuries. ^[23]

Énrí Ó Muirgheasa suggested that this area (Breifne) which is the nexus between Ulster and Connacht should be investigated as the genuine location where the Balor legend was localized, rather than Tory Island.^[24]

Balor's wife

Cethlenn is not explicitly called Balor's wife in the LGE,^{[14][25][lower-alpha 4]} but it is thus stated in the Ogygia (1685).^{[3][lower-alpha 5][3][lower-alpha 6]}

Prognostication

In the early modern Romance Oidheadh Chloinne Tuireann (OCT), Balor's wife (Céithlionn or Ceithlinn) identifies Lug as their grandson, and proclaims that once he comes into Erin, the days that they the Fomorians will remain in power are at an end.^[5][26]

Arthur C. L. Brown remarks on this prediction that comes true in the form of Balor's destruction by Lugh,^[27] but prefers not to make connection to the ancient version of the Cath Maige Tuired in which Lug uses a sling stone as the lethal weapon,^[28] but rather to a folktale version in which Lugh uses a spear crafted by a particular swordsmith named Gavnin Gow.^[29]