Military history of Ireland
The Vikings pillaged monasteries on Ireland's west coast in 795, and then spread out to cover the rest of the coastline. The north and east of the island were most affected. During the first 40 years, the raids were conducted by small, mobile Viking groups. From 830 on, the groups consisted of large fleets of Viking ships. From 840, the Vikings began establishing permanent bases at the coasts. Dublin was the most significant settlement in the long term. The Irish became accustomed to the Viking presence and culture and in many cases became allies, with intermarriage common throughout Ireland. A major Irish battle involving Vikings was fought at the Battle of Clontarf in 1014, in which a large force of Vikings and their Irish allies were defeated by the gathered Irish forces of Brian Boru, then the High King of Ireland along with a small contingent of Viking defectors. After this date Viking activity was sporadic with various Kings and nobles attempting to extend their power base. In 1099, Magnus Barefoot, the King of Norway, and his Viking army had successfully campaigned alongside their Irish allies against opposing Irish warbands. On his return his force was ambushed and killed on the north coast of Ireland.
Vikings
Popular, modern conceptions of the Vikings—the term frequently applied casually to their modern descendants and the inhabitants of modern Scandinavia—often strongly differ from the complex picture that emerges from archaeology and historical sources. A romanticised picture of Vikings as noble savages began to emerge in the 18th century; this developed and became widely propagated during the 19th-century Viking revival. Perceived views of the Vikings as alternatively violent, piratical heathens or as intrepid adventurers owe much to conflicting varieties of the modern Viking myth that had taken shape by the early 20th century. Current popular representations of the Vikings are typically based on cultural clichés and stereotypes, complicating modern appreciation of the Viking legacy. These representations are not always accurate — for example, there is no evidence that they wore horned helmets.