Castletown was originally the capital of the Isle of Man but was superceded by Douglas in 1874. The House of Keys building still stands and faces Rushen Castle. The castle dominates the town. Construction commenced around the reign of the last Norse King of Mann - Magnus III who died in the castle in 1265AD. It had been under Norse control since the 8th Century. However control passed to Scotland under The Treaty of Perth ending the 1263-1266 Scottish-Norwegien War.