These enclosures, known in Irish as ráth when formed from earthen banks and ditches, were the farmsteads of early medieval Ireland, typically dating from roughly the fifth to the twelfth centuries. A bank of raised earth, sometimes doubled or tripled in circuit, enclosed a family's dwelling and perhaps their livestock, marking out domestic territory in a period before villages were the dominant form of settlement. Mayo has hundreds of them, many still clearly visible as raised rings in fields, their original purpose long dissolved but their outlines preserved by the reluctance of later farmers to break ground that local tradition often held to be fairy territory.

The Ballinvoash example belongs to this widespread but persistently interesting class of monument. Raths are so numerous across Ireland that individual examples can seem unremarkable until you consider the cumulative picture they present: a densely settled, agriculturally active countryside in early Christian times, organised around kinship groups and cattle wealth rather than towns or manorial centres. In Connacht particularly, where poor soils and a fractured landscape made large-scale tillage difficult, these enclosed homesteads represent a way of life adapted to the terrain over generations. The earthworks that survive are essentially the fossilised property boundaries of farming families whose names are otherwise lost.