The Earldom of Castle Stewart was created in 1801 for the 9th Baron Castle
Stuart who became 1st Viscount Castle Stuart in 1793 and 1st Earl Castle Stuart in 1800. The Earl was related to the Marquess of Londonderry, another Irish peer. Lord Castle Stewart was descended from Lord Ochiltree, an illegitimate scion of the Stewart kings of Scotland.
Earls Castle Stewart (1801)
- Andrew Thomas Stuart, 1st Earl Castle Stewart (1725-1809)
- Robert Stuart, 2nd Earl Castle Stewart (1784-1854)
- Edward Stuart, 3rd Earl Castle Stewart(1807-1857)
- Charles Knox Stuart, 4th Earl Castle Stewart (1810-1874)
- Henry James Stuart-Richardson, 5th Earl Castle Stewart (1837-1914)
- Andrew John Stuart, 6th Earl Castle Stewart (1841-1921)
- Arthur Stuart, 7th Earl Castle Stewart (1889-1961)
- Arthur Patrick Avondale Stuart, 7th Earl Castle Stewart (b. 1928)
