John McDonald II was the last person to hold what title before it was claimed by the Crown in 1493?

The Lord of the Isles or King of the Isles is a title of Scottish nobility with historical roots that go back beyond the Kingdom of Scotland. It began with Somerled in the 12th century and thereafter the title was held by a series of his descendants, the Norse Gaels rulers of the Isle of Man and Argyll and the islands of Scotland in the Middle Ages.

They wielded sea-power with fleets of galleys. Although they were, at times, nominal vassals of the Kings of Norway, Ireland, or Scotland, the island chiefs remained functionally independent for many centuries. Their territory included much of Argyll, the Isles of Arran, Bute, Islay, the Isle of Man, Hebrides (Skye and Ross from 1438), Knoydart, Ardnamurchan, and the Kintyre peninsula. At their height they were the greatest landowners and most powerful lords after the Kings of England and Scotland.

The end of the MacDonald Lords came in 1493 when John MacDonald II had his ancestral homeland, estates, and titles seized by King James IV of Scotland. Since that time, the MacDonald Clan has contested the right of James IV to the Lordship of the Isles and uprisings and rebellions against the Scottish Monarch were common. More recently, the Lordship of the Isles has been held by the Duke of Rothesay, the eldest son and heir apparent of the King of Scotland, a title which, since the creation of the Kingdom of Great Britain, is usually borne by the Prince of Wales. Thus Prince Charles is the current Lord of the Isles.