Brian’s Northern Ascendancy
The most substantial dated evidence for the year is Brian’s campaign into Cenél Conaill, the north-western branch of the Northern Uí Néill associated above all with Donegal and neighbouring districts. The Annals of Inisfallen record “a great muster of the men of Ireland” by Brian, son of Cennétig, into Cenél Conaill. The army was divided: one part, under Brian’s sons Murchad and Domnall, harried the territory and carried much booty back towards Munster; Brian himself then went on to the lake, a detail that evokes the practical geography of campaigning in a land of rivers, loughs and routeways rather than neat frontiers.