Alexander Stewart was a Scottish nobleman, Earl of Mar from 1404. He acquired the earldom through marriage to the hereditary countess, and successfully ruled the northern part of Scotland.

There are currently two earldoms of Mar in the Peerage of Scotland, and the title has been created seven times. The first creation of the earldom is currently held by Margaret of Mar, 31st Countess of Mar, who is also clan chief of Clan Mar. The seventh creation is currently held by James Erskine, 14th Earl of Mar and 16th Earl of Kellie, who is also clan chief of Clan Erskine.