The lyrics are based on the legend of Fionnula, Lir's daughter who was turned into a swan by her stepmother Aoife. Lir was the father of the sea god Manannan. His first wife had four children. Lir's second wife, Aoife was jealous of the children and ordered her servants to kill them.

The servants refused and so Aoife transformed the children into white swans and laid a curse on them. They would spend three hundred years on the waters of Lake Derryvargah, three hundred on the Straits of Moyle (between Scotland and Ireland) and three hundred on the Atlantic by Erris and Inishglory. Only then, and when a "woman of the South mated with a man of the North" would the curse end. Although swans, the children still had the gift of speech and music.

On Erris Bay they were befriended by a hermit who taught them of Christianity. Deoca, the princess of Munster (in the North) became betrothed to Lairgnen, of Connacht (in the South). Deoca asked for the four singing swans as a wedding gift. Lairgnen seized the swans, and when they arrived they were transformed back into human beings. As they died the hermit baptized them and they ascended to heaven.*

For a complete list of tunes by Thomas Moore at this site see the Contemplator's Short Biography of Thomas Moore.

• The Contemplator's Short Biography of Thomas Moore
• Thomas Moore (with portrait)
• Moyle District Council
  Map, photos, and information.
• The Children of Lir
• Swan Maidens
  Myths of Swan Maidens from Europe (including Sweden, Germany, Romania and Serbia), China and India.
• Manannan Mac Lir
• Celtic Mythology
• Encyclopedia of the Celts