Sword of Light

Claíomh Solais (reformed spelling), Claidheamh Soluis (unreformed Mod. Ir. and Sc. Gaelic) (Irish pronunciation: [/kɫiːv ˈsɔɫɪʃ/]; an cloidheamh solais (variant spelling) pronunc. roughly /kleeve-solish/), rendered "Sword of Light", or "Shining Sword", or "a white glaive of light", is a trope object that appears in a number of Irish and Scottish Gaelic folktales.

The sword has been regarded as a legacy to the god-slaying weapons of Irish mythology by certain scholars, such as T. F. O'Rahilly: the anologue in the Irish Mythological Cycle being Lugh's sling that felled Balor, and their counterparts in heroic cycles are many, including the popular hero Cúchullain's supernatural spear Gae bulga and his shining sword Cruaidín Catutchenn.

A group of Sword of Light tales bear close resemblance in plot structure and detail to the Arthurian tale of Arthur and Gorlagon.

The folk tales featuring the claidheamh soluis typically compels the hero to perform (three) sets of tasks, aided by helpers, who may be a servant woman, "helpful animal companions", or some other supernatural being. The majority of are also bridal quests (or involve the winning of husbands in e.g., Maol a Chliobain).

The sword's keeper is usually a giant (gruagach, fermór) or hag (cailleach), who oftentimes cannot be defeated except by some secret means. Thus the hero or helper may resort to the sword of light as the only effective weapon against this enemy. But often the sword is not enough, and the supernatural enemy has to be attacked on a single vulnerable spot on his body. The weak spot, moreover, may be an external soul concealed somewhere in the world at large (inside animals, etc.), and in the case of "The Young King of Esaidh Ruadh", this soul is encased within a series of animals.

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