Liban was a mortal woman who turned into a mermaid. She was the daughter of the Firbolg King Euchad and his wife Etain who was the captured bride of Midhir, of the Tuatha de Danann tribe of Ireland.

After a sacred well overflowed, Liban was swept away by the water along with her pet dog. She found shelter in a cave by the Lough Heagh sea where she prayed to the Goddess Dana, Celtic "Mother of All",  that she would be turned into a salmon so she would be free to swim with the fish near her shelter.

Goddess Dana answered her prayers, you might say, halfway. Poor Liban was to remain a human from the waist up and  have the tail of a fish from the waist down. Her pet dog was transformed into an Otter.

For over 300 years Liban lived happily among the waves. Apparently, longevity was also part of the deal with Goddess Dana. At long last, Beoc, a clergy man who sailing for Rome heard her singing. When he stopped the ship, she rose up out of the water to ask him to deliver a message to the Bishop of Bangor containing a request to meet with the holy men in Rome.

Liban was carried from the Sea and taken to Beoc’s church, Teo-da-Beoc. Once there, she chose her moment of death and St. Comgall baptized her with the name, Murgen (Sea-Born).

Liban (Murgen) was named one of the "Holy Virgins" after she performed many miracles in the church of Teo-da-Beoc. To this day, the priests still celebrate Liban by displaying many statues and carvings of mermaids in her memory.