The earliest Uí Sheasnáin are very much associated with the area along the lower Shannon between Killaoe at the southern end of Lough Derg and Limerick city, the lowest bridging point on the River Shannon. Research carried out by Dr Cathy Swift of the University of Limerick points to two possible origins for the Uí Sheasnáin family. The first (the evidence for which is found in the 17th century Leabhar Mór na nGenealach) points to a Muinntir Uí Sheasnáin (muinntir meaning people or clan) who were located in east Clare. This Seasnán family, we are told, was established more than a thousand years earlier by a descendant of Cas, the man who gave his name to the Dál gCais, the ruling dynasty of Gaelic north Munster. Seasnán lived in the 13th century and traced his origins to Cas who lived in the 4th century through Aengus (6th century), Carthann Fionn Og Mór (5th century) and Blad, a son of Cas.
Because this genealogy was being written in the 1600s, over a thousand years after the time of Cas, it may have been entirely spurious and invented to place the Uí Sheasnáin firmly within the greater Dál gCais ‘tribe’ with its associations with 11th century Brian Ború. There may, of course, have been some truth in the Cas origin story. The Dál gCais were very much associated with the O’Brien (Ó Briain) family but even if the Uí Sheasnáin and Ó Briain are descended from Cas, that is not to say that there would be a genetic link between the two groups as Gaelic clans were not organised solely on the basis of kinship.
The second origin story that Swift has put forward is that the Uí Sheasnáin are descended from a singular individual, Seastnán, associated with the Uaithne Thíre, a people from the hilly Sliabh Fraoich area on the Tipperary side of the Shannon immediately north of Killaloe/Ballina, near the present day village of Portroe in the modern barony of Owney. Swift argues, in fact, that this is a far more credible foundation story as she is of the view that the Dál gCas story was probably invented centuries later to provide the Sextons – who by that time were a prominent Limerick City family – with an origin story that linked them to Gaelic ‘royalty’.
Whether the modern Sextons of the Clare/Limerick/Tipperary area are descended from either of neither of these origins is largely a matter of conjecture but advances in DNA testing may, in time, provide some further clarity. It does, however, seem plausible enough that at least one of these has some credibility.
The different Sexton groups
The precise nature of the relationship between the Sextons of the lower Shannon region of Thomand and the Sextons of Cork and Cavan has also yet to be determined but it is possible that these branches came about as a result of the political turbulence of the 17th century when the old gaelic systems were well and truly ripped apart with the consequent displacement of tens of thousands of people from their former ancestral locations.
We can be fairly certain that one particular family of Sextons moved into medieval Limerick City sometime around the mid 1400s as there is a historical record of this family as a result of Edmund Sexton becoming Mayor of the City and for a time an influential figure at the Court of Henry VIII (for more information on this branch of the Sextons, see the section on the Limerick City Sextons). There is also a reference to a Sexton who served as a quarter master to Eoghan Ruadh O Néill (Owen Rua O’Neill) who would have had a very different political outlook to that of his Limerick City Sexton contemporaries. One can only wonder whether this man might have been the originator of the Sextons who today live on the southern fringes of Ulster – in Cavan, in particular. Is it entirely coincidental that Eoghan Rua himself died in Cloughoughter, Co. Cavan in 1649? Or are the Cavan Sextons descended from the Colmán O Seasnáin, an 11th century poet of Meath and Ulster, mentioned in the Annals of the Four Masters? The same source also mentions (in Volume 1) a presumably separate Colman Ó Seasnáin, a Munster tutor to poets, who died in 661 and (in a later volume) a Niall Ó Seasnáin, a ‘learned senior’ of Munster, who died in 1084. There are references also in various Fiants of the time to a Thomas O Sisnane, 1601, a labourer of Kilcoman, Co Tipperary, to a John ro O Sisnane, 1601, of Garranvelly, Co Tipperary and to a Patrick O Shesnan, 1602, a yeoman – all mentioned .
Similar conjecture to that proposed above might lead us to speculate that the Sextons of Cork moved south at a broadly similar time when armies were amassing for the Battle of Kinsale. Whether they travelled with the Gaelic armies of O’Neill or O’Donnell or with the O’Brien forces who fought on the English side is unknown but by 1659, no fewer than 14 Sisnanes (an anglicisation of Seasnan) were recorded on Pender’s ‘Census’ as being among the Principal Irish Names in the West Division of the Barony of Carbery (the area between Clonakilty and the Mizen Head). We also know that a Donnell (Donal) O’Sisnane of Kinsale together with his son Teig O’Sisnane were among those shipped to Spain from Kinsale with Don John (Juan D’Aguilla) in March 1601 shortly after the decisive battle of Kinsale*. The Sextons who moved south in this way seem to have settled initially in the Donoghmore area of mid Cork and in the Timoleague/Barryroe area of west Cork. At a later point (perhaps the late 1700s), a number of Sexton families moved further west into the Skibbereen area. It is, of course, possible that the Cork Sextons are of entirely different origin to the Sextons of north Munster. They may have descended from a an indigenous Cork Seasnán of whom there is no record in any of the annals or indeed, the first Cork Sexton could even be of non-Irish settler origin (though this seems unlikely given that all the Cork Sextons are Catholic and that no record of any settlers by the name of Sexton is to be found in the extensive records of the Munster plantation or other English settlement). * [Emigrants to Spain, MS 601, p.235 – documents held at Lambeth Palace Library. Supplementary information: Calendar of the Carew Manuscripts preserved in the Archiepiscopal Library at Lambeth, ed J.S. Brewer & W. Bullen (6 vols., 1867-73), vol IV, document 205. Related information: Pacata Hibernia, p. 424.]
Sextons descended from the Protestant Limerick City branch certainly made their way to America as early as the first half of the 17th century and the fortunes of these Sextons are chronicled in a very detailed history entitled ‘ Early Sexton Roots in America’ by Velma Odeal Gehrke and freely available on the internet. These Sexton migrants predated later waves of Catholic Sextons (particularly from Clare and West Cork) who emigrated from Ireland in large numbers in the 19th and 20th centuries.
Surname mapping analysis carried out by Wilson shows that by the 1850s, the Sextons were found most commonly in Co. Cork followed by Clare, Limerick, Tipperary, Cavan and Kilkenny with much smaller concentrations found in Sligo, Kildare, Longford and Dublin. Much smaller numbers (often individuals) are found in a large number of other counties scattered throughout the country. Three curiosities are worth noting at this point: there are a few Tackney familes living in Co.Cavan; two Sisnanes (Catherine and Thomas) are recorded in Catholic Parish Baptismal Records as living in Templeboy Parish in Co. Sligo; and two Protestant Sexton households are recorded for Co. Kildare (all the Limerick City Protestant Sextons having either died out or having emigrated to the US or England). All other 19th century records denote members of the Ó Seasnáin clan as being both Sexton and Catholic.
What DNA analysis may in time reveal
As we have noted in passing above, there may, in fact, have been three quite separate foundation stories for the three main Sexton ‘clans’ (Lower Shannon Sextons, Cavan Sextons/Tackneys and Cork Sextons). The three groups may have had three quite separate unrelated ancesters – all coincidentally known as Seasnán. This is not at all implausible. It is well known for instance that there are a number of quite distinct and unrelated Murphy families and O’Donoghue families.
Modern genetic research has shown that families associated with the Dál gCais show a particular genetic anomaly that is common and quite possibly unique to the O Briain (O’Brien) and other Thomand families descended from Cas. This variation is known as Irish Type III DNA (R-L 226 cluster). What is interesting however is that analysis of the DNA of Con Sexton (of the West Cork Sextons) shows that he does not share this genetic variation and in fact has Irish Type II DNA (R-M 269) which is most commonly found in populations indigenous to the south west of Ireland. So there are two possibilities. One is that the Sextons of Lower Shannon origin are not genetically descended from Cas (ie the 17th century genealogists were wrong) and therefore may or may not be related to the Cork Sextons . The other is that the Sextons of Lower Shannon origin may yet be shown to be genetically descended from Cas – but in which case, it would seem, they cannot be related to the Cork Sextons.