In 1476 John MacDonald, the last MacDonald Earl of Ross, was created a Lord of Parliament as Lord of the Isles, but this title was forfeited to the Crown in 1493 and has since been reserved for the eldest son of the reigning monarch.
John MacDonald in 1469 gave a charter of the lands of Sleat on the Isle of Skye to his illegitimate half-brother Hugh, and Hughs direct descendant, the 8th Laird of Sleat, was in 1625 created a baronet as Sir Donald MacDonald of Sleat.
In 1776 his direct descendant Sir Alexander MacDonald of Sleat, the 9th Baronet, was raised to the peerage as BaronMacDonald of Slate (note the spelling change).