Kalends of January
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. AD 851.
Two successors of Patrick—two bishops of Ard Macha, i.e. Forannán, scribe, bishop and anchorite, and Diarmait, the most learned of all the teachers of Europe, rested.
Ard Macha was laid waste by the foreigners of Linn on the day following Summer-Lent.
The complement of eight score ships of fair-haired foreigners came to Snám Aignech, to do battle with the dark foreigners; they fought for three days and three nights, but the dark foreigners got the upper hand and the others abandoned their ships to them. Stain took flight, and escaped, and Iercne fell beheaded.
Maengal abbot of Ard Sratha, and Cenn Faelad, son of Ultán, scholar of Both Conais, and Lergal, superior of Othan, fell asleep.
Fogartach son of Mael Bresail, king of Airgialla, dies.
Cathal son of Dubán, king of Uí Duach of Argatros, dies.
Forbasach son of Maelodar, superior of Cell Mór of Cenn Eich, dies.
A slaughter was inflicted on the foreigners at the islands of eastern Brega, and another slaughter of them at Ráith Alláin by the Cianacht in the same month.