Courtenay was baptized on 30 August 1768, the fourth of 14 children (his siblings all being girls) [2] and was known as "Kitty" to family and friends.

With his new title and wealth, the young Lord Courtenay led an excessively flamboyant lifestyle.

John Swete (1752–1821) of Oxton House, Kenton in Devon, wrote of him in veiled terms as follows in connection with a discussion of the Parsonage House of the parish of Powderham:[3] Courtenay was described as follows by the genealogist Thomas Christopher Banks (1765–1854) in a letter to Lord Chancellor Brougham (1778-1868), who was an active force behind the decision of the House of Lords to revive the Earldom in his favour:[5] As a youth, 'Kitty' Courtenay was sometimes named by contemporaries as the most beautiful boy in England.

[6] Beckford, 8 years his senior, was a wealthy art collector and sugar plantation owner.

Courtenay took up residence in 1807, and from there watched the trial run of Robert Fulton's North River Steamboat.