The word "dún" in Irish place names almost always signals an ancient enclosed settlement, and Doonaha is no exception. Ringforts, known in Irish as "ráth" when earthen or "caiseal" when built of stone, were the dominant form of rural settlement in early medieval Ireland, roughly between the fifth and twelfth centuries. They typically consisted of a circular area enclosed by one or more earthen banks and ditches, and served as farmsteads for families of varying social rank. Thousands survive across the island in various states of preservation, tucked into field boundaries or rising unexpectedly from pasture land.

The Loop Head Peninsula, a narrow finger of land jutting into the Atlantic between the Shannon Estuary and Galway Bay, is an area with a long and layered human presence. The peninsula's relative isolation has meant that many of its older landscape features have endured where they might elsewhere have been ploughed away or built over. A rath in Doonaha fits naturally into that pattern, a remnant of the kind of settled agricultural life that once organised this coastline into individual family territories, each bounded and defined by earthworks that doubled as boundary markers and enclosures for livestock.