With Game of Thrones entering its final short seasons, showrunners David Benioff and D.B. Weiss are now working on ideas beyond the world of Ice and Fire. HBO announced today that the pair have gotten a series order for a drama called Confederate. The series will be set in an alternate America where the Southern states successfully seceded from the Union, slavery persists into the modern era, and the country is on the brink of a third Civil War.

According to HBO’s announcement, Benioff and Weiss have been working on the idea for years, initially intending on developing it into a feature film. In a joint statement, though, they say HBO was the right place to take the concept. “Our experience on Thrones has convinced us that no one provides a bigger, better storytelling canvas than HBO.”

The series will explore the tensions between the United States and the Confederate States of America, with characters living on either side of what’s known as the Mason-Dixon Demilitarized Zone. The cast will feature freedom fighters, abolitionists, journalists, and, of course, slaves and slave owners. Working on the show with Benioff and Weiss as executive producers are Nichelle Tramble Spellman (The Good Wife) and Malcolm Spellman (Empire).

‘Confederate’ sounds like a response to series like ‘The Man in the High Castle’ and ‘The Handmaid’s Tale’

Conceptually, Confederate sounds like a response to the recent crop of series like The Man in the High Castle and The Handmaid’s Tale, both set in alternate realities where the villains of history won. (It also closely resembles Ben Winters’ recent bestseller Underground Airlines, which also deals with slavery persisting in the South, in an alternate present-day America.) However, HBO is almost certainly courting controversy with the drama. Arguments have been made in recent years about the Hollywood landscape already being flooded with slave stories. What’s more, Benioff and Weiss have been heavily criticized for their treatment of people of color on Game of Thrones. It’s not clear the decision to greenlight this project will do much to address those criticisms.

Production for Confederate will begin after the final season of Game of Thrones, which may be pushed back in to 2019.