The flowering of English monastic culture was to come to an abrupt end because of political and military developments in Scandinavia. In the 8th century the Scandinavians became expansionist and began raiding neighbouring coasts. Initially this was simple marauding, plundering of places of wealth (usually seats of chieftains) and returning back to home base. With time they became more adventurous and, with the efficient and sea-worthy boats which they had, succeeded in making the crossing over the North Sea to Scotland. This was a qualitative change which was to have lasting consequences for the peoples of the British Isles. From this point onwards the Scandinavians are known as Vikings, a term deriving either from Frisian wic ‘settlement’ or Old Norse vik ‘bay’. The earliest attacks were on Lindisfarne and Jarrow in 793-4. Here it were the monasteries with their ornamental riches which attracted the raiders. They plundered and killed indiscriminately there and elsewhere, e.g. on the island of Iona, a centre of Hiberno-Scottish culture. Very soon the Vikings became the scourge of Ireland and the entire north of England.