It is a building that appears to have come into existence somewhere in the gap between two Ordnance Survey mappings, absent from the landscape as the cartographers recorded it in 1838, then firmly present, labelled simply as 'R.C. Church', by the time the 1920 edition was produced. That silence on the earlier map raises more questions than it answers.

The church at Béal Feirste, on the Mayo side of Achill Sound, the narrow channel separating Achill Island from the mainland, belongs to the broad wave of Catholic church-building that followed Catholic Emancipation in 1829. Before that legislation, public Catholic worship had operated under significant legal restriction, and the decades that followed saw congregations across Ireland raising permanent stone churches where they had previously made do with mass rocks, barn chapels, or open-air gatherings. The fact that no structure appears on the 1838 Ordnance Survey six-inch map, one of the most detailed cartographic undertakings of nineteenth-century Ireland, suggests the church was built sometime after that survey was completed, though precisely when remains unclear from what survives. By 1920, whatever the building's condition or active use, it was considered substantial enough to mark and name.