Deserted medieval settlements are among the more quietly significant categories of archaeological site in Ireland. They mark places where communities once organised their daily lives, farmed the surrounding land, and then, for reasons that varied enormously from place to place, ceased to do so. The physical traces left behind can range from pronounced earthworks and house platforms to little more than faint undulations in a field that only reveal themselves in low winter light or from the air.

Kilcolgan itself sits at the head of Kilcolgan inlet on the south Galway coast, a place with a long history of settlement and activity linked to both the sea and the fertile land inland. The broader region was shaped by the medieval land-holding structures of Connacht, where Gaelic and later Anglo-Norman patterns of occupation overlapped and shifted across the centuries. Deserted settlements in this part of Galway were sometimes the result of population collapse following the Black Death in the mid-fourteenth century, sometimes the consequence of later plantation-era disruption, and sometimes simply the gradual drift of communities toward more viable ground. Without more detailed site-specific information, it is not possible to say which circumstances apply here, but the classification as medieval places it within a broad window of roughly the twelfth to the sixteenth century.