John of Islay (or John MacDonald) (1434–1503), Earl of Ross, fourth (and last) Lord of the Isles, and Mac Domhnaill (chief of Clan Donald), was a pivotal figure in late medieval Scotland: specifically in the struggle for power with James Stewart, James III of Scotland, in the remoter formerly Norse-dominated regions of the kingdom. His defeat in this conflict led to rebellion against John by his illegitimate son Angus Óg, resulting in the defeat of John's fleet at the Battle of Bloody Bay in the early 1480s. Thereafter and until his death in 1503 John remained an inconsequential figure while, until his murder in 1490, Angus continued to dominate the affairs of Clan Donald. In 1493 James IV brought the Lordship of the Isles to an end.