816 - Inis Cathaigh was raided

Ireland
Inis Cathaigh was plundered by Danish vikings, they slaughtered the monks, and they defaced the holy monument of St. Senan.
The viking raids continued on Inis Catthaigh (Scattery Island) until the vikings were defeated in 1014 at Clontarf.
Spain

Northmen took part in a13-day conflict between Emir Al-Hakam and the Christian prince of Pamplona, Inigo Arista. According to the sources, the chieftain who led the Vikings in 816 was called Saltan (Halvdan), and he fell in the fighting. On both these occasions the Vikings participated as allies of the Basques.