These grounds, known in Irish as cillíní (singular cillín), were used for centuries to inter unbaptised infants, and sometimes others considered ineligible for burial in consecrated ground, including stillborn babies, the mentally ill, suicides, and strangers. The Catholic Church's doctrine of limbo held that unbaptised souls could not enter heaven, which meant that grieving families were often denied the comfort of a church burial. Instead, they found their own places at the margins, literally and figuratively, of the sanctioned world.

Cillíní tend to occupy liminal spots in the landscape, old ring-forts, boundary ditches, cliff edges, the shoreline above the tide line, places that were already understood as thresholds between one world and another. The sites were rarely formally marked in the way that church graveyards were, and burials were often carried out at night or in the early morning, quietly and without ceremony. The grief was real; the exclusion was not. Over time, many of these places were forgotten, absorbed into farmland, or remembered only in local oral tradition. The one at Doon is a recorded monument, which means it has been identified and noted as part of the archaeological landscape of Clare, even if its full history remains to be thoroughly documented.