Complex sentence: With the death of Guðrøðr, the Isle of Man came under Scottish rule which lasted at least until the death of Alexander III in 1285, as it was listed among Alexander's heir Margaret, Maid of Norway's future possessions in 1284.
Split into simpler sentences: With the death of Guðrøðr, the Isle of Man came under Scottish rule. This lasted at least until the death of Alexander III in 1285, as it was listed among Alexander's heir Margaret, Maid of Norway's future possessions in 1284.