Una Mannion was born the sixth of eight children in Philadelphia, Pennsylvania. She grew up in the Philadelphia area and attended Notre Dame Academy in Villanova. At 17 she headed south to study English at the University of the South in Sewanee, Tennessee and then returned to Philadelphia to do a Masters in English at Temple University.
Throughout her childhood, Una and her siblings spent summers visiting County Sligo, Ireland where their father was born. In the 1990s, Una settled there. For over twenty years she has taught at the Institute of Technology, Sligo. In 2014, Una joined the Sandy Field Writers’ and has been writing ever since. Recently, she completed an MA in Writing from NUI Galway and is programme chair of the new BA in Writing + Literature at IT Sligo. She lives in Sligo with her husband and three children.