Cairns of this type were raised across Ireland during the Neolithic and Bronze Age periods, most often as funerary monuments covering burial chambers, though some appear to have served as territorial markers or gathering points on ancient routeways. The name Cum itself is likely an anglicisation of the Irish "com" or "com", meaning a hollow or a corrie, that distinctive bowl-shaped depression carved into hillsides by glacial action, and the pairing of such a toponym with a prehistoric monument is not unusual in the west of Ireland, where the relationship between landscape and memory was taken seriously by the people who built here.

Beyond its classification as a cairn in the townland of Cum, the specific history of this particular monument, its dimensions, its date, whether it conceals a chamber or has been disturbed over the centuries, remains at present undocumented in publicly accessible form. That absence is itself a kind of information. Mayo contains hundreds of prehistoric monuments, many of them inadequately recorded, and the cairn at Cum is among those still waiting for fuller archaeological attention. What is known is that it exists, that it was considered significant enough to note, and that it occupies a county whose boglands and mountain slopes have preserved prehistoric structures in remarkable numbers.