Page "Amlaíb Cuarán" Paragraph 11

Amlaíb Cuarán's career began in 941, following the death of his cousin Amlaíb mac Gofrith, when he became co-ruler of York, sharing power with his cousin Ragnall son of Gofraid.

According to the Annals of Clonmacnoise, Amlaíb had been in Britain since 940, having left another son of Gofraid, Blácaire, as ruler of Dublin.