Dugan

Dugan or Duggan () is an Irish surname derived from Ó Dubhagáinn. The best known family of the name had its territory near the modern town of Fermoy in north Cork, and were originally the ruling family of the Fir Maighe tribal group which gave its name to the town. They claimed descent from Mug Ruith, the legendary magician of the Fir Bolg. They ceded pre-eminence to the O'Keeffe family in the eleventh century, but remained powerful in the area. Along with the other Fir Maighe families they lost their power when the Normans conquered the territory in the twelfth and thirteenth centuries. Provided by Wikipedia