These sites, known in Irish as cillíní (singular: cillín), were used for centuries across Ireland as informal burial places for unbaptised infants, stillborn babies, and occasionally others considered ineligible for Catholic churchyard burial, including suicides and strangers. They occupy a quietly marginal space in the landscape, often sited at townland boundaries, beside old ringforts, or on ground already felt to carry some ancient sanctity. The one at Cloonsheerea belongs to this scattered and understudied tradition.

The practice of cillín burial reflects a long and painful intersection of Catholic doctrine and rural Irish custom. Canon law, as it operated in Ireland well into the twentieth century, held that those who died without baptism could not receive a Christian burial. Families, unwilling to leave their infants entirely unmourned, turned instead to these liminal places, some of which had been used since the early medieval period and were associated with pre-Norman ecclesiastical sites or enclosures. The grief attached to such places was largely private; the burials were rarely marked, and the sites were maintained by local memory rather than by any official body. In many parts of the west of Ireland, cillíní continued in use into the mid-twentieth century.