November 24th , 1265
Magnus Olafsson, also known as Magnus III, was the last King of the Isle of Man, and he died in 1265. Magnus ruled over the Isle of Man during a time of political turbulence in the region. The Isle of Man is a self-governing British Crown Dependency located in the Irish Sea.
Magnús was a member of the Crovan dynasty—a line of Norse-Gaelic sea-kings whose kingdom encompassed the Isle of Man (Mann) and the northern parts of the Hebrides, from the late eleventh century to the mid thirteenth century.
He was a son of Óláfr Guðrøðarson, King of the Isles, and a member of the Crovan dynasty. Magnús’ realm encompassed Mann and parts of the Hebrides. Some leading members of Magnús’ family—such as his father—styled themselves “King of the Isles”; other members—such as Magnús and his brothers—styled themselves “King of Mann and the Isles”. Although kings in their own right, leading members of the Crovan dynasty paid tribute to the Kings of Norway and generally recognised a nominal Norwegian overlordship of Mann and the Hebrides. Magnus was driven out by King Alexander III.
Magnus Olafsson’s reign was marked by conflicts with other regional powers, including the Kingdom of Scotland (Alexander III) and the Kingdom of England (Henry III of England).
Treaty of Perth
Three years after the inconclusive skirmish at Largs, terms of peace were finally agreed upon between the kingdoms of Norway and Scotland. On 2 July 1266, with the conclusion of the Treaty of Perth, the centuries-old territorial dispute over Scotland’s western seaboard was at last settled.
Within the treaty, Magnús Hákonarson, King of Norway (died 1280) ceded the Hebrides and Mann to Alexander, who in turn agreed to pay 4,000 merks sterling over four years, and in addition to pay 100 merks sterling in perpetuity. Other conditions stipulated that the inhabitants of the islands would be subject to laws of Scotland; that they were not to be punished for their actions previous to the treaty; and that they were free to remain or leave their possessions peacefully
Ultimately, in 1266, the Treaty of Perth was signed between Magnus and King Alexander III (4 September 1241 – 19 March 1286)of Scotland. The treaty ceded the Isle of Man to Scotland in exchange for other territorial concessions.
This marked the end of the independent kingship of the Isle of Man, and it became subject to the authority of the Scottish crown. The Isle of Man’s subsequent history involves various influences and rulers, including periods of rule by the English and later the British Crown.