The Soghain were a people of ancient Ireland. Dubhaltach Mac Fhirbhisigh identified them as part of a larger group called the Cruithin, and stated of them: Of the Cruithin of Ireland are the Dál Araidhi (Dál nAraidi), the seven Lóigisi of Leinster, the seven Soghain of Ireland, and every Conaille (see Conaille Muirtheimne) that is in Ireland.
The location of four of the seven Soghain is as follows:
The Soghain of Connacht were located in Tír Sogháin, and area in central east County Galway bounded by the river Suck on the east, the river Clare on the west; the Grange and Shiven rivers to the north; the Raford and Ballinure rivers to the south. A poem recorded in The Book of Uí Maine, Cruas Connacht clanna Sogain, lists the kingdom's boundaries, which can be found to tie in with the above locations:
The previous, pre-Gaelic people of the area were called the Senchineoil. Very little information survives on them.
The Soghain of Connacht were described by Seán Mór Ó Dubhagáin in his poem Triallam timcheall na Fodla where he states:
The six Sogain let us not shun/their kings are without oblivion/Good the host of plundering excursions/to whom the spear-armed Sogain is hereditary.
The Book of Lecan lists their six branches as Cinel Rechta, Cinel Trena, Cinel Luchta, Cinel Fergna, Cinel Domaingen and Cinel Deigill.
The genealogy of Saint Kerrill of Cloonkeekerrill is given as Caireall mac Curnain mac Treana mac Fionnchada mac Nair mac Earca mac Tiobraide mac Sodhain Salbhuidhe mac Fiacha Araidhe. His grandfather, Treana mac Fionnchada, was the eponym of the Cinel Trena, who were apparently located close to Knockma as evinced by the placename Tír Mhic Trena (the land of the sons of Trena). This area was the western limit of the kingdom of the Connacht Soghain.