We've almost reached 2014, and as part of the many celebrations that will occur next year, we will be commemorating the Battle of Clontarf where Brian Boruimhe defeated an army of Vikings and Leinsterman trying to undermine his efforts to maintain a singular authority over all the men of Ireland.
Of course much has been made of this battle in Irish historiography and in the formation of Irish identity in the 19th century. Originally, perhaps as a result of the effective propagandising efforts of the author of Cogadh Gaedhel re Gallaibh,it was viewed as an Irish verse Viking affair, the struggle for national freedom against a foreign enemy.
Subsequent scholarship, however, has undermined its national significance, downplaying the threat that Vikings posed at the end of the 10th century, and that it was primarily about Brian asserting his overlordship, and a rebellion against those attempts, as opposed to a genuine attempt by Dublin Vikings and their Islander allies to reassert their position.
Seán Duffy's new book, Brian Ború and the Battle of Clontarf, is in some respects a revision of the revisionism. Firstly, he reasserts the importance of Brian's achievement. Not merely did he ride roughshod over the status quo, the first non-Eoghanacht king of Munster since the 5th century, the first non-Uí Néill (high-)King of Ireland ever. Before the rebellion that lead to Clontarf, Brian had the unprecedented distinction where every provincial king, as well as the kings of Bréifne, Ulaidh and Osraige, of Ireland had come into his house (i.e. had submitted to him). This seems to have involved Brian providing each with a tuarastal, literally a wage, but more akin to a movable fief, and receiving military service and tribute (mainly in the form of cattle, but silver, foodstuffs and billeting rights could also be included). There is evidence to suggest that Brian had officials in other provinces, maeraibh, in order to regularly collect his dues (although this was nothing peculiarly new).
Although Seán Duffy does characterise the actions of Maelmordha King of Leinster, and his nephew, Sitriuc Silkbeard king of Dublin which lead to Clontarf as a rebellion against Brian's hitherto unchallengeable authority, he does recognise that even amongst contemporary annalists the battle of Clontarf was given national and international significance. The annalists describe Brian as leading the men of Ireland and Maelmordha and Sitriuc's forces were frequently referred to as "Na Gaill" in brief. It seems too that the annalists, rather than say that Sitriuc supported his uncle, claim that the rebellion itself was at the instigation of the Dubliners.
Of course, on their own the Leinstermen and the Dubliners could not face down Brian's forces, for which he could potentially draw on all corners of Ireland, however, the addition of Norse Islanders from the Western Isles and Orkney stiffened their resistance. This is quite similiar to the situation in 1167 where Mac Murchadha, who could not challenge Ua Conchobhair in the field (the latter again could potentially drawn on all the polities of Ireland for his armies), looked abroad in order to maintain his independence.
The arrival of Norse mercenaries and allies of Sitriuc naturally evened out the playing field. Contemporary accounts suggest Sitriuc's army, along with his Norse and Leinster allies, consisted of up 7,000 men, the majority of which being heavily armed Norse warriors. Of course, this may have initially been motivated by a desire to break Brian's control over the country, however, a victory at Clontarf would have left them with a strong army with the only military force capable of challenging them decimated and in a shattered retreat. This is no small number, and Svein Forkbeard in England had demonstrated what a force of 10,000 Viking warriors could do even with a united, coherent and full armed enemy.
In short, although the battle of Clontarf may not have been fought to prevent a conquest of Ireland, it seems the victory itself, though pyrrhic, may have prevented a reassertion of Norse power in Ireland, something that seems to have been appreciated by contemporary accounts both at home and abroad.