Mark O'Neill was born in 1963. During his early days he lived in England, Mauritious, South Africa, Nigeria and Malta. Mark studied at Kingston College of Art, London and graduated with First Class Honours. He worked for a time in London as an illustrator, during which time he illustrated the cover of six Catherine Cookston novels.
Mark now lives in County Wexford. He first exhibited in Forge Gallery in County Louth and subsequently has had sell out exhibitions in the Frederick Gallery in Dublin. Annually, Mark has had exhibitions in Wexford, coinciding with the Wexford Opera Festival.