EXCLUSIVE: Downton Abbey creator Julian Fellowes, a man who knows a thing or two about writing about the wealthy, has set his sights on the richest family in history for his next project.

I hear that Fellowes is developing a TV series about the Rothschild banking dynasty, who, in one generation, rose from the deprivation of the ghetto to become the richest and most powerful family in history. Fellowes is collaborating on the script with Ian Kelly (Mr Foote’s Other Leg).

Five Arrows is being produced by Jemima Khan, through her new production company Instinct Productions, and 42, the production company behind BBC and Netflix animation Watership Down and Channel 4’s forthcoming Michael Stuhlbarg and Matt Lauria-fronted drama Jerusalem.

The drama series is understood to be in development with Sky Atlantic.

The family saga is one of the ultimate rags-to-riches tales, set against the backdrop of war and revolution. It tells the story of how the family became to possess the largest private fortune in the world during the 19th century.

The family gained pre-eminence in the bullion trade during the Napoleonic Wars between 1803 and 1815 and Nathan Mayer Rothschild almost single-handedly financed the British war effort. It will also tell the story of European Jewry and the triumph over antisemitism as well as portray a story about human relationships, fraternal struggles for dominance, of brilliant but disenfranchised women, of generational conflict, of incestuous alliances and of forbidden love with outsiders.

Khan also knows a thing or two about dynastic families, having been born Jemima Goldsmith, the eldest child of Lady Annabel Vane-Tempest-Stewart and banker Sir James Goldsmith, whose family made its money in merchant banking in the 16th century. The European editor-at-large of Vanity Fair and associate editor of the New Statesman launched Instinct Productions with Princess Productions founder Henrietta Conrad this year and Five Arrows is its first project.

Khan was previously the exec producer of the BAFTA-nominated documentary We Steal Secrets: The Story of Wikileaks by Alex Gibney and co-produced Unmanned: America’s Drone Wars & Making A Killing: Guns, Greed and the NRA and the play, Drones, Baby, Drones at The Arcola Theatre.

An interesting fact linking Fellowes with the Rothschilds is Highclere Castle, which was the fictional setting for Downton Abbey, is owned by the eighth earl of Carnarvon, whose ancestor the fifth earl of Carnarvon married Almina Wombwell, the illegitimate daughter of Alfred de Rothschild, the grandson of the banking empire’s founder.

Fellowes is currently working on NBC’s long-gestating period drama The Gilded Age, which will launch in 2019, while production is set to start this year on the feature film version of Downton Abbey. He is also adapting The Girl On The Landing into a TV series with The Fyzz Facility. He is repped by UTA and 42.