Julius Soubise was the son of a Jamaican slave from St. Kitts in the Caribbean, who was brought to England in the 1760s by Captain Stair Douglas. At ten years old, Soubise was given to the Duchess of Queensbury who treated the child like her own son. She and her husband Charles dressed and educated young Julius, teaching him how to fence and ride horses. Soubise was popular among the rich and successful of Queensbury.
Soubise was taught the violin, proper speech and singing by the best instructors. He would label himself “The Black Prince,” taking relationships with many women, one of which was rumored to be the Duchess of Queensbury.
Soubise was a pioneer of a cultural movement among gentleman in England called “The Black Dandies.” These were slaves who were brought to the country and taught the white culture. His personality and likeability was the subject of several pieces of literary and stage work, one of which was the 1769 opera The Padlock by Isaac Bickerstaffe; A Mungo Macaroni (1772) by Matthew and Mary Darly and William Austin’s 1773 book The Duchess of Queensbury and Soubise.
Soubise stayed in England until he fled in 1777. Only two days after he left, the Duchess of Queensbury died. Soubise himself lived until 1798 when he died from injuries after a riding accident.