Researchers have recently used the mathematical techniques of social network theory to analyze an 1800s translation of Cogadh Gaedhel re Gallaibh, a medieval Irish text describing warfare between an army led by Irish king Brian Boru, regional Irish kingdoms, and Viking invaders. They asked a simple question: was the fighting during this period a civil war among the Irish, or a defensive war against Viking newcomers?
The medieval Cogadh Gaedhel re Gallaibh describes how King Boru succeeded in unifying Ireland by 1011, but rebellion in Leinster and Viking-controlled Dublin led to the Battle of Clontarf in 1014. Boru’s army was victorious, although the king was killed during the battle. In recounting all this, the text gives us many characters, both Irish and Viking, and their relationships to one another. The research team used those relationships and applied social network theory, which measured to what extent the Irish and Viking characters in the text were linked to each other.
Statistical analysis of the contacts between the hundreds of Irish and Viking characters, and the more than 1,000 connections between them in Cogadh Gaedhel re Gallaibh, indicates that overall, the conflict was between the Irish and Vikings. Irish-on-Irish conflict did exist. Leinster did rebel after all. But the overarching pattern was of Irish fighting Vikings, not each other.
