<P> There are various competing theories that have addressed the early colonisation process, although it is clear that the Northern Isles were the first to be conquered by Vikings and the last to be relinquished by the Norwegian crown . Thorfinn Sigurdsson's rule in the 11th century included expansion well into north mainland Scotland and this may have been the zenith of Scandinavian influence . The obliteration of pre-Norse names in the Hebrides and Northern Isles, and their replacement with Norse ones was almost total although the emergence of alliances with the native Gaelic speakers produced a powerful Norse - Gael culture that had wide influence in Argyll, Galloway and beyond . </P> <P> Scottish influence increased from the 13th century on . In 1231, an unbroken line of Norse earls of Orkney ended and the title was since held by Scottish nobles . An ill - fated expedition by Haakon Haakonarson later in that century led to the relinquishing of the islands of the west to the Scottish Crown and in the mid-15th century Orkney and Shetland were also transferred to Scottish rule . The negative view of Viking activities held in popular imagination notwithstanding, Norse expansion may have been a factor in the emergence of the Gaelic kingdom of Alba, the forerunner of modern Scotland, and the trading, political, cultural and religious achievements of the later periods of Norse rule were significant . </P> <P> The Northern Isles, known to the Norse as the Norðreyjar, are the closest parts of the United Kingdom to Norway and these islands experienced the first and most long - lasting Norse influence of any part of Scotland . Shetland is some 300 kilometres (190 mi) due west of Norway and in favourable conditions could be reached in 24 hours from Hordaland in a Viking longship . Orkney is 80 kilometres (50 mi) further to the south west . </P> <P> Some 16 kilometres (10 mi) due south of Orkney is the Scottish mainland . The two most northerly provinces of mainland Scotland, Caithness and Sutherland, fell under Norse control at an early date . South of there the entire western seaboard of mainland Scotland from Wester Ross to Kintyre was also subject to significant Scandinavian influence . </P>

Where did the vikings first land in scotland