Celebrity historian Dan Snow has revealed a fascinating fact about the only other Duke of Sussex from 150 years ago.

Prince Augustus Frederick, born in 1773, was the only Duke of Sussex until Prince Harry was given the title in five years ago.

Historian Dan Snow revealed on Twitter that Prince Augustus had been a "royal rebel".

The revelation comes as Prince Harry continues to ruffle feathers with his new autobiography. 

He said: “The only other Duke of Sussex was a royal rebel.

"Brother of the Duke of Cambridge, he was liberal in his politics, married unsuitable women without royal permission. Twice.

The Argus: Portrait of Prince Augustus Frederick from 1798Portrait of Prince Augustus Frederick from 1798 (Image: Guy Head)

“In old age he was Queen Victoria's favourite uncle. Still, they retired the title for a century and a half.”

Prince Augustus became Duke of Sussex in 1801 but the title became extinct on his death in 1843.

The title was picked up by Harry 175 years later in May 2018.

A poll by YouGov for The Times revealed that 44 per cent of people said that Prince Harry should be have his title removed after a series of revelations in a six-part Netflix series and his book released today, called Spare.