When the Vikings sailed to England and Ireland in the late 8th and early 9th centuries their most natural path was by the Orkneys and Shetlands and round the Western Islands of Scotland. We have seen how early they formed settlements in the Shetlands, and they soon reached the Orkneys and the Hebrides. From the Orkneys they crossed to the mainland, to Sutherland and Caithness--the very names bear witness to Scandinavian occupation--while Galloway (i.e. the land of the Gaill-Gaedhil, _v. supra_, p. 56) was settled from the Isle of Man. Already in the 9th century the Norse element in the Hebrides was so strong that the Irish called the islands _Innsi-Gall_ (i.e. the islands of the foreigners), and their inhabitants were known as Gaill-Gaedhil. The Norsemen called the islands _Suðreyjar_ (i.e. Southern Islands) in contrast to the Orkneys and Shetlands, which were known as _Norðreyjar_, and the name survives in the composite bishopric of 'Sodor' and Man, which once formed part of the archdiocese of Trondhjem in Norway. The Isle of Man was plundered almost as early as any of the islands of the West (_v. supra_, p. 12), and it was probably from Man that the Norse settlements in Cumberland and Westmorland were established. Olaf the White and Ívarr made more than one expedition from Ireland to the lowlands of Scotland, and the former was married to Auðr the daughter of Ketill Flatnose who had made himself the greatest chieftain in the Western Islands. After the battle of Hafrsfjord, when Harold Fairhair had finally crushed his rivals in Norway itself, so powerful were the Norse settlements in the West that he felt his position would be insecure until he had received their submission. Accordingly he made a great expedition to the Shetlands, Orkneys and the west coast of Scotland, fulfilled this purpose and entrusted the Northern Islands to Sigurd, brother of Rögnvaldr, earl of Möre, as his vassal.