In 1625, the title of Earl of Annandale had been created for John Murray, but it became extinct when his son James died without heirs.

Johnstone's son, also James, resigned the earldom and received a regrant of the title, as Earl of Annandale and Hartfell, in 1661, and a further regrant of the same title, but by crown charter, in 1662 to his heirs male of the body, whom failing, his heirs female of the body.

The Committee for Privileges ruled that Charles II's 1662 charter of regrant of lands constituted the creation of a new title.

The title therefore descended through the female line in the person of Lady Henrietta Johnstone (who married Charles the First Earl of Hopetoun) to Patrick Hope-Johnstone.

The heir apparent is the present holder's son David Patrick Wentworth Hope-Johnstone, Lord Johnstone (b.