Acknowledged by Malcolm III as part of the Kingdom of the Isles, a Norwegian crown dependency, from the 12th century onwards Norwegian power in the Western Isles weakened. By the 1266 Treaty of Perth they reverted to the Scottish crown control under the tutelage of the quasi-autonomous "Lordship of Garmoran" (ruled by the MacRory, a faction among the rulers of the Kingdom of the Isles). In 1427, following violence between the MacRory heirs to Garmoran (Clan Ranald, the Siol Gorrie, and Siol Murdoch), Garmoran was declared forfeit.