A cashel is simply a ringfort built from stone rather than earth and timber, the word itself coming from the Latin castellum by way of Old Irish. Where earthen ringforts, or raths, were thrown up across Ireland in their thousands between roughly the fifth and twelfth centuries, cashels tend to cluster in areas where stone was easier to come by than good cutting timber, and Clare, with its limestone-rich terrain, has its share of them.

Ringforts were the farmsteads of early medieval Ireland, enclosures within which a family and their livestock sheltered, the surrounding wall offering protection against opportunistic cattle raiders as much as any formal military threat. The cashel at Drumgloon belongs to this tradition, a circular or near-circular enclosure whose perimeter wall would once have defined the boundary between the domestic world within and the wider, less ordered landscape beyond. Thousands of such sites survive across the country in varying states of preservation, some reduced to a faint crop mark visible only from the air, others still carrying substantial sections of their original masonry.