is today known as the Machars. The entire region would have thus stretched from the North Channel to Wigtown Bay, and would have likely encompassed an area similar to the modern boundaries of Wigtownshire. Earlier in the century, the entire region may have formed part of Sitriuc's realm, and various Irish and Welsh sources indicate that it may have been held by one of the latter's two sons named Amlaíb. If Echmarcach was indeed the son of Ragnall mac Gofraid, and succeeded his father sometime in the 1030s, Echmarcach may well have first gained control of the Rhinns when he apparently began his domination of the Irish Sea region in 1036 (the year he first seized Dublin). Even if such a chronology is correct it does not necessarily mean that Echmarcach owed his rule in the Rhinns to ancestral connections in the Isles—it could have instead derived from his new-found position in Dublin. Although in practice, the collection of cáin could be undertaken without the displacement of an underking, if "rex Innarenn" indeed refers to the Rhinns it could reveal that, after having been defeated by Murchad on Mann, the defeated Echmarcach fled to this mainland region. Furthermore, if Echmarcach was a native of what is today the south-west of Scotland, the title could be evidence that, on the collapse of Echmarcach's once expansive kingdom, Echmarcach proceeded to entrench himself in the protection of his native home. Margaðr and Guthormr Gunnhildarson Echmarcach has sometimes been identified as a certain Margaðr who appears in various mediaeval sources documenting the contemporary Irish Sea adventures of Margaðr and Guthormr Gunnhildarson. One such source is Haralds saga Sigurðarsonar, within Heimskringla. According to this source, Margaðr was King of Dublin, and a close friend of Guthormr, an accomplished man who was a nephew of the Norwegian kings Óláfr and Haraldr Sigurðarson. Late one summer, the saga relates that Margaðr and Guthormr took part in particularly successful raid in Wales. As their loot of silver was being assessed, Margaðr demanded Guthormr's share, forcing the latter to fight for his portion of the plunder. Although outnumbered sixteen ships to five, the saga relates that, through the miraculous intervention of God and Guthormr's saintly uncle (Óláfr), Guthormr was able to defeat and slay Margaðr and all his followers in the ensuing battle. The fateful encounter between Margaðr and Guthormr is sometimes dated to 1052 on the presumption that