It is a listed monument, formally recognised by the state, and yet the details that would ordinarily accompany such a designation remain unavailable. The name itself offers the only real clue. Cornamonaster contains the Irish word manistir, derived from the Latin monasterium, suggesting that this corner of Mayo was once associated with monastic or ecclesiastical activity, a pattern common across the west of Ireland where early Christian communities left their mark on placenames long after the physical structures they inhabited crumbled or were absorbed into farmland.

Without available documentation, the specifics of the church's age, construction, and history cannot be stated with any certainty. What can be said is that Mayo has a deep ecclesiastical landscape, with early medieval church sites often consisting of little more than a ruined nave, a fragment of wall, or a small graveyard enclosed by a roughly circular boundary, the shape of which can betray origins reaching back to the early Christian period. Whether Cornamonaster fits this pattern, or represents something later, a post-medieval parish church perhaps, remains an open question until fuller records are accessible.