Nuada, called Nuada Airgetlam, Nuada of the Silver Arm, is a king of the Tuatha De Danann in Irish mythology, a god of kingship and rightful sovereignty, and his story turns on a principle deeply rooted in early Irish thought: that a king must be physically whole and unblemished. In the First Battle of Mag Tuired, fought against the Fir Bolg for the possession of Ireland, Nuada loses an arm; and because a maimed man could not, by the ancient rule, remain king, he is compelled to give up the sovereignty, and the kingship passes for a time to the half-Fomorian Bres, whose harsh and ungenerous rule the people come to resent. Nuada's arm is then restored by the divine physician Dian Cecht, who fashions for him a fully working arm of silver, the source of his epithet, and in a further version the physician's son Miach, more skilled still, causes an arm of living flesh and blood to grow in its place, healing him completely and making him again whole and fit to rule.
Restored, Nuada resumes the kingship. His story reaches its end at the Second Battle of Mag Tuired against the Fomorians: recognising that the young, many-skilled god Lugh is better suited to lead the Tuatha De Danann against the terrible Fomorian champion Balor, Nuada yields command to him, and Nuada himself is killed in the battle by Balor's destroying eye. Nuada's sword is remembered as one of the four great treasures of the Tuatha De Danann, from which none could escape once it was drawn. He embodies the sacred requirement of the whole and rightful king, and the wisdom of a ruler who steps aside for a greater champion when the need of his people demands it.