From the late eighth to the early eleventh century Ireland was preyed upon by the Vikings; fierce pagan warriors and raiders from the north who founded Ireland’s first cities and opened up trade with the wider world.
In the eighth, ninth and tenth centuries, the rich monastic islands fell prey to marauding Viking fleets. Following an initial phase of exploratory raiding beginning in the late 8th century Viking invasion and settlement began from the mid-9th century onwards with the foundation of longphoirt (ship harbours) at several locations on the coast. While Viking efforts to conquer large portions of Ireland ultimately failed they did result in the establishment of several coastal towns, including Dublin, Wexford, Waterford and Limerick, and the adoption of many Scandinavian loan-words and seafaring techniques by the native Irish. Outside the acknowledged areas of Scandinavian settlement a Viking warrior’s grave with shield and dagger have been discovered in the Connemara sand dunes at Eyrephort and a Viking Rune Stone was incorporated into a house on Beginish Island off the Kerry Coast.
Viking influence on Irish material culture is also visible in the appearance of a Hiberno-Scandinavian style of dress and decoration reflected in a Hiberno-Norse ringed pin discovered on Omey Island some years ago. The Viking Age in Ireland is generally taken to have ended in 1014 CE with the defeat of the united armies of Leinster, Viking Dublin and the Northern Isles at the battle of Clontarf by the army of Brian Boroimhe, a ruler of the Dal Cais Sept in Munster who had usurped the high kingship. In fact however, Viking settlers remained in Ireland after Clontarf although the fleets and armies of the Viking towns fell progressively under the dominion of the more powerful Irish rulers. Indeed, the most significant Viking impact on Ireland may have come indirectly in 1066 when a Scandinavian army landed in northern England to seize the country for Harold Hardrada of Norway. Although this invasion was defeated at the battle of Stamford Bridge on 25 Sept 1066, it left the English army weakened before their encounter with William of Normandy at Hastings in October of the same year. The Norman Conquest of England and subsequently Wales introduced a new factor into the affairs of Ireland.