The very existence of a church on an island of this size, somewhere off the coast of County Mayo, points to a pattern common along Ireland's western seaboard: early Christian and medieval communities that chose island locations deliberately, whether for the spiritual discipline of remoteness or the practical shelter a small landmass could offer against the pressures of the mainland.

Island churches in Mayo often trace their origins to the early medieval period, when monasticism spread through the Atlantic fringe of Europe and hermits or small communities of monks sought out difficult, marginal places. Some were later adopted as parish churches serving scattered island populations that persisted well into the post-medieval centuries. Without more detailed documentation for this particular site, the building's age, its dedication, and the precise history of the congregation that once used it remain genuinely uncertain. What can be said is that Inishdaff, like many of its counterparts along this coastline, carries the kind of quietly loaded archaeology that accumulates on islands where the sea has always made continuity difficult and departure, eventually, inevitable.