For nearly 100 years after the arrival of the Normans in 1169AD the old world of Gaelic Ireland was in retreat. The Normans brought to Ireland superior weapons, the long sword, lance, Welsh crossbows, and iron helmets, and chain mail protecting much of the body. This was in contrast to the native Irish with their axes and short swords and dressed in linen tunics. To halt the Norman onslaught the remaining independent Irish Chieftains needed a new weapon and they found it in the mercenary warriors from the Western Isles of Scotland. These Gallowglass or ‘foreign Gaels’ had served as elite warriors in the Western Isles of Scotland for over 100 years prior to their arrival in Ireland.

The first 160 Gallowglass, who appear to have been from Clan MacDoughall arrived in Ireland in 1259AD as part of Dougall MacSorley’s (King of the Hebrides) daughters dowry in her marriage to Aedh O’Connor, the then King of Connaught. The Gallowglass fought like the Normans protected in mail coats and iron helmets, see Figure. But they were notable with their characteristic two handed axes and Claymores (a large 2 handed sword). This trickle of warriors became a flood as many mercenary Gallowglass Clans either sought new lords after backing the losing side in the Scottish wars of Independence or just somewhere to ply their trade, and given the battle against the encroaching Normans or the constant inter-Clan warfare there was always a demand for the services  in Ireland.

Many Clans like the McCabe’s and MacSweeney’s transplanted completely to Ireland, see Figure. The MacSweeney’s vacated their homeland around Castle Swin on the Argyll peninsula in Scotland for life in the service of the O’Donnell’s in Donegal. Others remained seasonal travellers appearing in the spring and summer offering their services to the highest bidder (everybody appears to have decided that making war in autumn and winter in Ireland was a bad idea). While others like the MacDonald’s/MacDonnell’s’ and MacNeill’s established territories in County Antrim in the northeast of Ireland to complement their lands in Scotland (the MacNeill’s appear to have been the new occupants of Swin Castle vacated by the MacSweeney’s). County Antrim provided the shortest crossing point between Scotland and Ireland and the presence of Scottish Clans there may have been an attempt to monopolise this lucrative trade.

What is certain is that the tide had turned, the Norman Conquest had lost momentum, and the Irish Chiefs with the aide of their new weapon rolled back the Normans. By the 14^th and 15^th Centuries a stalemate developed, with Ireland divided into spheres of influence as reflected in the medieval ethnicity map of Ireland, see Figure. There was a mini Gaelic revival and although not all the Normans adopted Gaelic ways and customs, the habit of hiring Gallowglass was adopted by all, including the English authorities who’s rule was restricted to the area known as ‘The Pale.’ Some of the Gallowglass Clans had by this time become independent establishing their own territories.

But who were these warriors who effectively changed the course of Irish history, and how can you tell if you are descended from them? Clues as to the origins of the Gallowglass can be found in the surname of the first to arrive; the MacDoughall’s, who’s surname translates as ‘son of the dark foreigner.’ This indicates that they were descendants of Vikings (foreigners) who settled in the western highlands and Islands of Scotland, who had intermarried with the Gaels they found there and adopted their Gaelic language and customs, but had still retained the fearlessness and fighting prowess of their Viking forebears. So if you know what to look for you can reveal whether you are directly descended from these fearless Norse-Gaels.

Firstly one can examine surnames, history records the most notable Gallowglass were from the Clans of McCabe, MacDonald/McDonnell, MacDougall/McDowell, MacRory, MacSheehy, MacSweeney, and McCoy. But this was a trade that continued for over 400 years and many Scots Clans got in on the act, so how does one identify other Clans and surnames associated with Gallowglass? Luckily these Scots-Gallowglass can be readily distinguished from the later Scottish settlers that flooded Ireland as part of the Plantation of Ulster in the 16^th and 17^th Century. This is simply because these later arrivals were Protestant and spoke English, in contrast to the Catholic faith and Gaelic language of the native Gaels and earlier Gallowglass. Religious and language differences meant that these two people rarely mixed which was reflected 300 years later in the 1911 census that showed that Planter surnames could readily be identified based on their 88% Protestant religious affiliation. So if you have a Scottish surname and recent Irish ancestry, and that surname demonstrated a protestant religious affiliation significantly less than 88% in 1911, then your ancestors may well have been Gallowglass. Surnames that fit these criteria are shown in Figure.

But this surname and historical approach is flawed, leaving one with statistical probabilities. For conclusive proof one must explore commercial ancestral DNA testing. The ancestral DNA test that can establish your Gallowglass-warrior credentials is the Y-DNA37 test. This test looks at the Y chromosome which is passed from father to son through the generations. What you get with the results of that test are the names of people with whom you share a common male ancestor. Typically one will match many individuals with many different surnames, but how can one share a common ancestor with people with different surnames? The answer is quite simple; when one’s direct male ancestor first took his surname approximately 1000 years ago, his neighbours some of whom he shared ancestry with, crucially picked other surnames. Hence one’s ancestors neighbours are reflected in the DNA results, and since surnames can still be found concentrated in the area they first arose, plot where the surnames as revealed by the Y-DNA occur and you’ll reveal where your direct male medieval ancestor lived.

So if you have Irish ancestry your closest Y-DNA37 matches may reflect your ancestor’s presence in his ancient Clan territory. But if you have a paper trail showing recent Catholic Irish ancestors and a Scottish sounding surname like MacDonald, McNeill, or McSweeney, your DNA results may reflect your ancestors earlier presence in Scotland when he assumed his Scottish-Gaelic sounding surname. But if they were indeed descendants of Viking’s your Norse ancestry will also be reflected in earlier or more distant matches to Scandinavian individuals, thus reflecting your ancestor’s earlier presence in Norway (or Denmark) and conclusively establishing your warrior credentials.  

This sounds logical in principal but can commercial ancestral DNA results truly reflect this? The answer again is Yes, I analyse peoples DNA results professionally for a living and found my first Case Study with clear Gallowglass ancestry in the most unlikely of places. The surname of the individual in question was ‘Terry,’ which is associated with Norman settlement in Ireland. The family has a genealogical paper trail that places their recent Irish ancestors in County Waterford on Ireland’s south coast. However the Y-DNA test revealed that Mr Terry is part of the 50% of males who’s Y-DNA does not match their (Terry) surname. His association with the Terry surname is a result of a non-paternal event (e.g. adoption or infidelity) that occurred at some point in his distant paternal ancestry. Mr Terry’s closest DNA matches were to overwhelmingly Scottish surnames, and specifically with the MacNeill’s and the area around Swin Castle on the Kintyre peninsula in the Western Isles of Scotland. Strikingly his more distant matches included many of clear Scandinavian origin and others with Scandinavian surnames. His paternal ancestors were the Vikings who settled in Scotland, who adopted the Gaelic language and customs, and served in Ireland as mercenaries. They left evidence of their presence in the DNA of the Irish people and their descendants, even those with a paper trail leading back to Waterford.

The association with Waterford is interesting as the last private battle fought in Ireland, between the Norman Butler’s and Fitzgerald’s took place near the town of Affane in County Waterford in 1565AD, not far from where Mr Terry’s recent Irish ancestors originate. Both sides fought with contingents of Gallowglass, and since the tradition of ‘Coyne and livery’ was to quarter the Gallowglass amongst the local population, this tradition most probably led to the non-paternal event in Mr Terry’s ancestry. The Butlers carried the day, but this battle marked the beginning of the end of the Gaelic way of life (including the bad Irish habits adopted by the old English/Normans). Queen Elizabeth was furious that her subjects (particularly her cousin Lord Butler) could wage war without royal consent. This crackdown resulted eventually in the Plantation of Ulster which took place in part to halt the flow of Gallowglass to Ireland and prevent the Irish and Norman lords from waging war!

The Terry Case Study can be downloaded from the Irish Origenes website. I am Dr Tyrone Bowes and DNA and ancestry has always been my passion. I have created the Irish, Scottish, and English Origenes websites to help people to rediscover their heritage using commercial ancestral DNA testing (A Welsh Origenes website will be launched in December 2012).

This article was written by me (Dr Tyrone Bowes) for the September Issue 2012 of the Celtic Guide.