The Vikings, a Scandinavian people of astounding vitality, first began their invasion of Scotland in 794. However, the first wave of mass Viking migration occurred around 888, when King Harold of Norway defeated an unruly faction of northern clans who then abandoned their homeland. In search of a new place to live, they migrated to the sea-swept Orkney Islands in the north of Scotland under the leadership of their chief, Earl Sigurd. This settlement was permitted by the Scottish king and the kings of the Isle of Man, who allowed the Viking exiles to make their homes in the Orkney and Shetland Islands in return for a payment of 20,000 shillings.
However, the Vikings defaulted on this payment--an action which resulted in much bloodshed in the following years. This broken oath was not the only cause for conflict. Motivated by their thirst for land, the aggressive Vikings pushed their way onto the mainland and gained a foothold in Caithness. Battling the native Picts and Dalriadans, the Vikings roved as far southward as Northumbria in England. The north of Scotland was used by Thorfinn Rollo as a base from which to attack the east coast of England prior to his success in Normandy. King Malcolm Ceanmore of Scotland managed to unite the clans of the Scottish/English borderlands around 1057, and drove the Viking invaders back northward to Sutherland.
The integration of the Viking people into Scotland was a long, difficult process, characterized by long-running feuds with the native Scots. The Vikings constantly remained aloof from the royal court of Scotland in Edinburgh. However, they were not unlike the native clans of highland Scotland in this regard, and they themselves came to be known as highlanders. As much as any other people, the robust Vikings are considered to be one of the founding peoples of the nation of Scotland.
- Swyrich, Archive materials