A rath, or ringfort, is a roughly circular enclosure defined by one or more earthen banks and ditches, built during the early medieval period, roughly between the fifth and twelfth centuries, and used as a defended farmstead by a family of some local standing. Ireland has tens of thousands of them, yet each one occupies a specific patch of ground with its own particular history, and the one at Drumdigus is no exception.

Ringforts are among the most common archaeological monuments in Ireland, and Clare has a considerable number scattered across its parishes. They functioned primarily as enclosed homesteads rather than military fortifications, the bank and ditch serving to keep livestock in and opportunistic raiders out. The word rath specifically refers to an earthwork construction, distinguishing it from a cashel, which is built from dry stone. Over centuries many were levelled by ploughing or absorbed into field boundaries, while others survived because local tradition held them to be fairy forts, places it was considered deeply unwise to disturb. That superstition, however unscientific, preserved a remarkable number of sites that would otherwise have been lost entirely.