The story of the foundation of Normandy is obscure: still more obscure is the origin and history of the leader of the Northmen at this time. Norse tradition, as given by Snorri Sturluson, makes Rollo to be one Hrólfr, son of Rögnvaldr earl of Möre, who was exiled by Harold Fairhair and led a Viking life in the west. Norman tradition, as found in Dudo, made him out the son of a great noble in Denmark, who was expelled by the king and later went to England, Frisia and Northern France. Dudo's account of the founding of Normandy is so full of errors clearly proven that little reliance can be placed on his story of the origin of Rollo. The _Heimskringla_ tradition was recorded much later, but is probably more trustworthy, and it would be no strange thing to find a man of Norse birth leading a Danish host. Ragnarr Loðbrók and his sons were Norsemen by family but they appear for the most part as leaders of Danes. How Rollo came to be the leader of the Danes in France and what his previous career had been must remain an unsolved mystery. His name is not mentioned apart from the settlement of Normandy. The Normans continued to ravage Brittany without any interruption and they were soon granted the further districts of Bayeux, Seez, Avranches and Coutances, which made Brittany and Normandy conterminous. CHAPTER V THE VIKINGS IN IRELAND TO THE BATTLE OF CLONTARF (1014) In the history of the Vikings in Ireland we have seen how the attempt made by Turges to bring all Ireland under one ruler came to nought by his death in 845. At first this seems to have thrown the Norsemen into confusion and we hear of a series of defeats. Then, in 849, the invasions developed a new phase. Hitherto while the Irish had been weakened by much internecine warfare, their enemies had worked with one mind and heart. Now we read of 'a naval expedition of seven score of the Foreigners coming to exercise power over the Foreigners who were before them, so that they disturbed all Ireland afterwards.' This means that the Danes were now taking an active part in the invasions of Ireland, and we soon find them disputing the supremacy with the earlier Norse settlers. A full and picturesque account of the struggle is preserved for us in the second of the _Three Fragments of Irish Annals_ copied by Dugald MacFirbis. Unfortunately the chronology of these annals is in a highly confused state and it is often difficult to trace the exact sequence of events.