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:
- A branch in the territory of Fernmag (barony of Farney, County Monaghan).
- In Delvin (County Westmeath) where a Soghain tribe lived with a branch of the Delbhna in an area called Trícha cét na Delbna Móire agus na Sogan.
- The Corcu Shogain, who were subject to the Benntraige under the Eoghanacht. An Ogham inscription discovered near Aglish in the barony of Muskerry, some twelve miles west of the city of Cork, displays the words MUCOI SOGINI, which probably means of the Corcu Sogain.
- The Soghain of Connacht were located in central east County Galway, in a kingdom called Tír Sogháin.
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:
- From Áth an Ibar west
- to Glais Uair Arnaigh
- was the extent of Sodhan
- that sword-guarded land.
- From Béal na Róbe in Maenmagh
- to the clear, soft-reeded Simin
- was the breath of the plain
- which bore no ignominy.
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.
Early Christian evangelists among the Soghain included Conainne, St Connell and Kerrill. Their successors include Naomhéid, Cuana of Kilcoonagh, Dubhán, Felig, Íbar, Íomar of the Sogain, Laisren of Cloonkerrill, Maol Chosna, Modiúit, Menott, Molua of Kilmoluagh.
Parishes known to be included in Tír Sogháin were:
Tír Sogháin became subject to the Uí Maine sometime during the first millennium.
- 811. Irghalach, son of Maelumha, lord of Corca Soghain;
- Clann Fhergail
- Uí Fiachrach Aidhne
- Clann Taidg
- Conmhaícne Mara
- Delbhna Tir Dha Locha
- Muintir Murchada
- Trícha Máenmaige
- Uí Díarmata
- Cóiced Ol nEchmacht
- Síol Anmchadha
- Maigh Seola
- Cenél Áeda na hEchtge
- The Book of Uí Maine, otherwise called 'The book of the O'Kellys', R.A.S. Mac Alister (ed.), Dublin, 1942.
- Punann arsa part i, Martin Finnerty, Galway, 1951.
- The parish of Ballinasloe, Rev. Patrick K. Egan, Dublin and London, 1960. Facsimile reproduction, Galway, 1994.
- Ballymacward:The story of an east Galway parish, John S. Flynn, 1991.
- The Life, Legends and Legacy of Saint Kerrill: A Fifth-Century East Galway Evangelist, Joseph Mannion, 2004. 0 954798 1 3
- The true identity of Saint Kerrill of Clonkeenkerrill, Joseph Mannion, in Making shapes with slates and marla:A Gurteen anthology, John and Margaret Corbett (compilers), Galway, 2004.
- The Senchineoil and the Soghain: Differentiating between the pre-Celtic and early Celtic Tribes of Central East Galway, Joseph Mannion, Journal of the Galway Archaeological and Historical Society, Volume 58, pp. 165–170, 2006.