Estimates suggest there were once around 40,000 of them across the island, built roughly between 500 and 1200 AD as enclosed farmsteads for families of some local standing. The circular earthen bank, or sometimes a drystone wall, defined a domestic space, a place for a household, its animals, and its stores. That so many survive at all, even as low grassy rings barely legible from ground level, is partly down to the deep unease that surrounded them in later folklore. Raths were widely believed to be the dwelling places of the fairies, and that reputation kept the plough away for centuries.

The Lissanair example sits in a county already densely layered with early medieval remains. Clare's landscape, particularly the limestone karst of the Burren to the north, preserves an unusual concentration of ancient field systems, cashels (stone-built ringforts), and souterrains, the narrow underground passages sometimes found beneath or adjacent to ringforts, likely used for cool storage or refuge. The rath form is slightly different, typically constructed from raised earthen banks rather than stone, and tends to appear across the more fertile lowland areas. The placename Lissanair itself carries traces of this past: "lios", from the Irish, is one of the most common words for a ringfort or enclosure, suggesting the feature was significant enough to name the land around it.