[1] The Earls Castle Stewart claim to be the head representatives in the pure male line of the Scottish Royal House of Stuart.

His grandson Andrew Stewart was created Lord Avondale circa 1499, a revival of the title which had become extinct on his great-uncle's death in 1488.

In compensation for the loss of this title, in 1619 the King created the previous 3rd Lord Ochiltree the Baron Castle Stuart in the Peerage of Ireland.

He was succeeded by his son, the second Baron, Andrew Stewart (1590–1639), who one year before the death of his father had in 1628 been created a Baronet in the Baronetage of Nova Scotia.

The second Baron made his home at Roughan Castle and was the founder of nearby Stewartstown, County Tyrone.

His eldest son, Sir Andrew Stewart 2nd Bt., became the third Baron and Governor of Fort Falkland in County Offaly fighting as a Royalist in the Civil War.

She married Henry Howard, 5th Earl of Suffolk, and the majority of the Stewart estates in Ireland were swallowed up by him.

The title Baron Castle Stuart passed briefly to Sir Andrew's brother, Josias Stewart, who died childless.

Instead, the de jure 7th Baron made his home at Irry, which he renamed Stuart Hall, near Stewartstown, County Tyrone.

The Earldom and Baronetcy of castle Stewart are registered with the Crown Office (now Ministry of Justice), and recorded at the College of Arms, London.

The heir presumptive is the present holder's paternal cousin, Thomas Harry Erskine Stuart (b.