 Alistair Carrach MacDonald of Keppoch took an active part in supporting his brother, Domhnall of Islay, Lord of the Isles, in claiming the Earldom of Ross.The result was that upon the death of Domhnall, Lord of the Isles in 1425 the Lordship of Lochaber was forfeited to the Crown and then the Crown bestowed it on the natural son of Stewart, Earl of Mar.This grant was later cancelled but the Lordship of Lochaber did not revert to Alistair Carrach MacDonald but instead was given to the Lord of the Isles who subsequently granted the lands of Lochaber to the chief of Clan Mackintosh and this was confirmed by the Crown.