His son JOHN OF ATHOL, by his share in the death of Bishop Adam of Cathnes, forfeited the southern portion of that province, the new county of Sutherland (1222); and on his murder, for his Scottish disregard of the Odal claims of his Orkneyan relatives (1231), his son-in-law MAGNUS II., son of Gilbert Earl of Angus, was acknowledged Jarl of Orkney by Hacon IV. of Norway, and of Cathnes by Alexander II. of Scotland. Five generations of this race of ANGUS ruled Orkney and Cathnes during a century of unwonted peace, arising from this double vassalage, the minorities and civil wars which weakened both Norway and Scotland, and the treaties of matrimony and commerce which united them. This calm was scarcely disturbed by the last Northman Viking-storm, which swept over the Islands to expire at Largs in the equinoctial gales of 1263, but which is memorable to Orkney for the Survey of its Urislands, and the Deathbed of Hacon, the last of the Sea-Kings. MAGNUS JARL III. had little difficulty in making his peace with his royal namesake of Norway, for his lukewarm support of an invasion so violent, and his grandson JOHN II. married a daughter of King Erik of Norway. The prudence of Robert the Bruce, Hacon V., and the young MAGNUS JARL V., hastened by mutual compensation and a new treaty (1312) to restore peace, when Scottish pirates seized and held to ransom Sir Berner Pess, the Norwegian Governor of the Islands during the Earl’s nonage, and Orkney had retaliated by a similar outrage upon Patrick of Mowat, a Scot—perhaps the first introduction of two names now common in the Islands. During this period of comparatively peaceful intercourse, many other Scottish names and fashions found entrance, and many distinctive Scandinavian features disappeared in Orkney, though still prevalent in Zetland, which was less exposed to Scottish influences. The male line of ANGUS JARLS failed in MAGNUS V., and their curtailed Jarldom passed by a female heir to the Scottish EARLS OF STRATHERNE, and from them to their representatives, ALEXANDER DE ARTH, who inherited and resigned the Earldom of Cathnes to Robert II. (1375–6), and HENRY LORD SINCLAIR, whose homage as EARL OF ORKNEY was, after an interval of disputed succession, accepted by Hacon VI. (2nd August 1379), but on conditions which left to him little beyond the lands of his fathers. Even their title, the only hereditary title permitted in Norway to a subject not of the Blood Royal, was declared to be subject to the Royal option of investiture. The Earl was to govern the Islands and enjoy their revenues, but only under Norse laws, and during the King’s pleasure; to keep in pay soldiers for the King’s service, but to make no war, build no place of strength, make no contract with the Bishop, nor sell nor impignorate any of his rights without the King’s consent; and finally, to answer for his administration to the King’s Court at Bergen. But the civil broils which preceded the Union of Calmar, and were