The one at Boleyboy in County Mayo belongs to a category of site known in Irish as a cillín, a place where, by long custom, unbaptised infants and others excluded from formal Christian burial were laid to rest. These grounds occupy a particular and melancholy corner of Irish social history, reflecting the theological anxieties and community practicalities of centuries during which the Catholic Church denied church burial to those who had not received the sacrament of baptism. Parents, rather than leave an infant without any marking of its passing, would bury the child quietly in one of these liminal places, often at field boundaries, on ancient earthworks, or at the edges of townlands.

The practice was widespread from the medieval period well into the twentieth century, and sites like the one at Boleyboy were rarely formally recorded or maintained in the way that parish graveyards were. They tend to survive as low, sometimes barely perceptible enclosures, occasionally with small uninscribed stones, their locations preserved largely through local memory. The townland name Boleyboy derives from the Irish, with "buaile" referring to a seasonal grazing place or summer pasture, suggesting land that was worked but perhaps never fully domesticated, the kind of marginal ground where a cillín might naturally be sited.