The two actresses have signed on tho co-star in the film, along with Nicole Beharie ("Shame," the upcoming "42").
"Room" takes place during the U.S. Civil War and centers on three Southern women – two white sisters and one African American slave -- who defend themselves from rogue Union soldiers who have broken off from the main army in order to plunder and pillage the land.
It was written by Julia Hart and will be directed by Daniel Barber ("Harry Brown"). Jordan Horowitz of Gilbert Films and Matt Williams, David McFadzean, Judd Payne and Dete Meserve of Wind Dancer will produce. Sierra/Affinity will handle international sales.
Principal photography is scheduled to begin in March in North Carolina.
"I am thrilled to be working with these three fantastic actors, and very excited to be directing this great script,” said Daniel Barber in a statement.
"'The Keeping Room' is a cinematic, thrilling, and dangerous piece of material," added Horowitz, "and we could not be more excited with the team that has come together to bring this unique story to the screen.”
“We are thrilled to be part of this special project filled with profound themes," Sierra/Affinity CEO Nick Meyer summed up. "Barber is a talented up-and-coming filmmaker, and we look forward to seeing his vision of the material realized.”
Wilde will next be seen opposite Jim Carrey and Steve Carell in "The Incredible Burt Wonderstone," before co-starring with Chris Hemsworth in Ron Howard's "Rush."
Steinfeld, who was nominated for an Oscar for the Coen Brothers' "True Grit," will soon be seen as Juliet in "Romeo and Juliet" and in the sci-fi adaptation "Ender's Game," with Harrison Ford and Ben Kingsley.