Following the Viking attack on the holy island of Lindisfarne in 793, the Vikings raided the mother abbey of Iona in the Hebrides, within the Gaelic kingdom of Dalriada, just a year later. The Picts was unable to come to Iona’s aid and the Vikings raided again and again. The Vikings had already established a bridgehead on the Shetlands and Orkneys, and they saw the Hebrides as a platform for raids across the Irish Sea. Throughout the 9th century increasing numbers of Norse settlers arrived in the Hebrides. In 839 a Norse army is said to have defeated a Gaelic-Pictish alliance. This defeat led to a union between Dalriada and Fortriu (the kingdom of the Picts), forming ‘Alba’, the incipient kingdom of Scotland. In 875 the Norwegian ruler Harald Finehair (or Fairhair) annexed Orkney (Orkneyjar), Shetland and the Hebrides to the Norwegian crown. Orkney became a major Norse earldom, and at times the semi-autonomous rule of its powerful earls extended down the west coast of Scotland, as far as the Isle of Man. In Sudreyjar (“southern isles”), or the Kingdom of the Isles, Norse settlers intermarried with native Gaels, exchanging language and culture, and becoming Norse-Gaels, the ancestors of the Gaelic-speaking peoples of the Hebrides. By the 10th century the earldom of Orkney included large amounts of territory on the Scottish mainland, the high point of Viking Scotland.
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