Amlaíb Cenncairech

Amlaíb Cenncairech was a Norse ruler and presumably King of Limerick notable for his military activities in Ireland in the 930s, especially in the province of Connacht and apparently even in Ulster and Leinster. This period, the 920s and 930s, is commonly regarded as the very height of Norse power in Ireland, and was when Limerick essentially equalled Dublin in power.

His epithet Cennc(h)airech is commonly translated into the unflattering "Scabby-Head" but this may be inaccurate. The adjective cairech actually means, according to the Dictionary of the Irish Language, "criminal; guilty; sinful", and thus Cennc(h)airech may be translated "Sinful Head".

Amlaíb is mentioned by name only in the Annals of the Four Masters and Annals of Clonmacnoise. Historians believe the dating in both cases is off. In general, the sources for western Ireland's history are not great. The Chronicon Scotorum records several of the same and related events but does not mention Amlaíb by name.

The Annals of the Four Masters are generally off by two years.

The traditional interpretation of these notices, the second immediately following the first in the manuscripts, is that what Amlaíb mac Gofraid was actually doing was compelling or recruiting Amlaíb Cenncairech for his upcoming battle with Athelstan of England. This was the Battle of Brunanburh.

More recent historians tend to interpret this as the culmination of an extended conflict between the Norse of Dublin and Limerick, dating from the arrival of Tomrair mac Ailchi in 922. They assume that the two Amlaíbs actually engaged in a battle and that mac Gofraid won a "decisive victory" over Cenncairech, effectively ending Limerick as a major player in Ireland for the next two or three decades.

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