I read somewhere that raiding Irish pirates were a problem for Roman Britain. Did the vikings make technological advances in the meantime or did the inhabitants of Ireland become more peaceful? Or, indeed, what?
Well during the time the Danes were raiding and sending larger invasion expeditions to England they were doing the same in Ireland. I'm not sure that the Irish raiders were non existent afterwards but I would be loath to say that they were not preoccupied with their own Danish 'infestation'. When the danes came to Ireland they sought to occupy and settle the land the same as they did in England.