Deserted medieval settlements are among the quieter categories of archaeological monument: no dramatic towers, no legible inscriptions, often nothing more than soil-marks, slight earthwork ridges, or the faint geometry of former enclosures visible from the right angle in the right light. The name itself carries a clue. Lios, in Irish placename tradition, refers to a ringfort or enclosure, the kind of defended farmstead that formed the basic unit of early and medieval rural life across Ireland. That the word survived into the modern placename suggests the feature was prominent enough, or remembered clearly enough, to anchor local geography long after the settlement itself was gone.

Deserted medieval settlements in the west of Ireland were abandoned for reasons that varied by place and period. Plague, shifts in land use, the displacement of Gaelic communities during and after periods of colonial plantation, or simple economic failure could each empty a townland of its people. The Connacht landscape is scattered with such sites, many of them unexcavated and poorly documented, their histories recoverable only in outline. Without specific records for this particular site, it is not possible to say when Lios Arúla was last inhabited, who lived there, or what the precise nature of the settlement was. What can be said is that the classification as a medieval deserted settlement places it within a broad span running roughly from the twelfth to the sixteenth or seventeenth centuries, a period during which rural Connacht saw considerable disruption and reorganisation.