"At the close of the 10th and beginning of the 11th century the battles of Tara and Clontarf overthrew the power of these Norsemen (or Ostmen as they were called) in Ireland, and restored the authority of the native Irish sovereign. About this time they [the 'Hy-Ivar,' or sovereigns of the island-empire of the Northmen—see above: 8-9TH CENTURIES] became Christians, and in the year 1066 we find one of their princes joining Harald Hardrada of Norway in his invasion of England, which ended so disastrously in the battle of Stamford Bridge. Magnus of Norway, thirty-two years later, after subduing the independent Jarls of Shetland and the Orkneys, attempted to reassert his supremacy along the western coast. But after conquering Anglesea, whence he drove out the Normans [from England] who had just made a settlement there, he crossed to Ireland to meet his death in battle. The sovereignty of the Isles was then restored to its original owners, but soon after split into two parts—the Suderies and Norderies (whence the term Sodor and Man), north and south of Ardnamurchan Point. The next glimpse we have of these dominions is at the close of the 12th century, when we find them under a chief named Somarled, who exercised authority in the islands and Argyleshire, and from him the clans of the Highlands and the Western Isles love to trace their ancestry. After his death, according to the Highland traditions, the islands and Argyleshire were divided amongst his three sons. Thus the old Norse empire was finally broken up, and in the 13th century, after another unsuccessful attempt by Haco, King of Norway, to re-establish the authority of the mother kingdom over their distant possessions, an attempt which ended in his defeat at the battle of Largs by the Scottish king, Alexander III., they were ceded to the Scottish kings by Magnus IV., his son, and an alliance was cemented between the two kingdoms by the marriage of Alexander's daughter, Margaret, to Eric of Norway." At the north of Scotland the Jarls of Orkney, in the 11th century, "conquered Caithness and Sutherland, and wrested a recognition of their claim from Malcolm II. of Scotland. Their influence was continually felt in the dynastic and other quarrels of Scotland; the defeat of Duncan, in 1040, by the Jarl of Orkney, contributing not a little to Duncan's subsequent overthrow by Macbeth. They fostered the independence of the north of Scotland against the southern king, and held their kingdom until, in 1355, it passed by the female line to the house of Sinclair. The Sinclairs now transferred their allegiance to their natural master, the King of Scotland; and finally the kingdom of the Orkneys was handed over to James III. as the dowry of his bride, Margaret of Norway." _A. H. Johnson, The Normans in Europe, chapter 2._