He was the son of Charles Hope, 1st Earl of Hopetoun and Lady Henrietta Johnstone.

[2] His paternal grandparents were the former Lady Margaret Hamilton (a daughter of the 4th Earl of Haddington) and John Hope of Hopetoun, who purchased the barony of Niddry from George Seton, 4th Earl of Winton and the neighbouring barony of Abercorn, with the office of heritable sheriff of the County of Linlithgow.

[5] In 1747 he was appointed Curator bonis (trustee in Lunacy) for his half-uncle, the 4th Earl of Annandale and Hartfell.

Before her death on 16 March 1767, they were the parents of:[6] His third marriage was to Lady Elizabeth "Betty" Leslie, (d. 1788) on 10 June 1767.

[9] Together, they were the parents of:[6] Lord Hopetoun died on 12 February 1781 and was succeeded in his titles by his son, James Hope-Johnstone.