Art Streiber / HBO

"Game of Thrones" showrunners David Benioff and D.B. Weiss are moving from one HBO fantasy world to another.

When "Thrones" ends, the two will write and executive-produce "Confederate," a series about an alternate-history timeline where the American South's secession was successful.

"As the brilliant 'Game of Thrones' winds down to its final season, we are thrilled to be able to continue our relationship with Dan and David, knowing that any subject they take on will result in a unique and ambitious series," said HBO programming president Casey Bloys on Wednesday. "Their intelligent, wry and visually stunning approach to storytelling has a way of engaging an audience and taking them on an unforgettable journey."

In the show, slavery remains legal in the Confederate States of America.

"The story follows a broad swath of characters on both sides of the Mason-Dixon Demilitarized Zone — freedom fighters, slave hunters, politicians, abolitionists, journalists, the executives of a slave-holding conglomerate and the families of people in their thrall," HBO said in a press release.

"We have discussed 'Confederate' for years, originally as a concept for a feature film," Benioff and Weiss said in the release. "But our experience on 'Thrones' has convinced us that no one provides a bigger, better storytelling canvas than HBO. There won't be dragons or White Walkers in this series, but we are creating a world, and we couldn't imagine better partners in world-building than (producers) Nichelle and Malcolm (Spellman), who have impressed us for a long time with their wit, their imagination and their Scrabble-playing skills."

Reaction on social media was wary.

remind me to stay off the internet the day when Ed Sheeran cameos as a slave trader in CONFEDERATE. — david ehrlich (@davidehrlich) July 19, 2017

I for one can't imagine an Alternate History where there are monuments to Confederate leaders all over America. — Sigh Hersh (@Ugarles) July 19, 2017

To be fair, "Confederate" will likely condemn every racist human on Earth in an artful, thought-provoking way. It's just hard these days. — Cassandra Nicholson (@WriterWarrior) July 19, 2017

Me, a writing teacher: There are no bad ideas, just bad execution--

HBO's Confederate: *exists*

Me: *opens mouth, shakes head, walks away* — Shana Mlawski (@ShanaMlawski) July 19, 2017

I'm just hoping that with Confederate, DB and Benioff look to Nichelle and other writers for guidance. Not so much discretion on GoT — Carli Velocci (@velocciraptor) July 19, 2017

please cast Vincent Kartheiser as the evil confederate general — thebluehoodie (@thebluehoodie) July 19, 2017

Underground gets cancelled and this Confederate show gets to happen? pic.twitter.com/Y2pvr1aSAz — Sage (@Sage_Simone) July 19, 2017

#Confederate sounds like "Man in the High Castle" but w US civ war. Why not just pick up @UndergroundWGN if you want to explore slavery @HBO — Bradley (@bgjamison) July 19, 2017

This is one of those ideas that could end up amazing or absolutely cringeworthy. https://t.co/Jcjq4ocmp5 — Jamelle Bouie (@jbouie) July 19, 2017

file this under: shows that seem like a good idea to a room full of white men https://t.co/GihdsG54Cp — Lisa Peterson (@lisatweeterson) July 19, 2017

Y'all: @HBO y'all need a show with more black people



HBO: Bet. https://t.co/HGtEMfk8EB — Final Breastination (@Suite_Tea) July 19, 2017

Feels like HBO should greenlight my show, in which the African slave trade never existed, as parity: https://t.co/kE50GNSwvO — Marc Bernardin (@marcbernardin) July 19, 2017

Confidential to HBO: Nobody on here thinks #Confederate is a good idea. — David M. Perry (@Lollardfish) July 19, 2017

They literally just announced this new Confederate show by the Game of Thrones creators and I'm already exhausted by the takes — Patrick Wyman (@Patrick_Wyman) July 19, 2017

Amazon's "Man in the High Castle," based on the novel by Philip K. Dick, also has an alternative-history premise, where World War II was won by the Axis Powers and Nazi Germany and Imperial Japan rule the United States. That similarity didn't go unnoticed.

HBO: Phil, Can I copy your homework?



Philip K. Dick: Yeah just change it up a bit so it doesn't look obvious you copied.



HBO: Ok pic.twitter.com/rOIOqsMwo3 — roger 🤔🤔 (@iamtherog) July 19, 2017

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