Bradley Whitford, Jaimie Alexander, Jack McBrayer and Hal Holbrook co-star.
Caviezel will play the real-life early 1900s aristocrat Ward Allen, who develops an unexpected partnership with freed slave Christmas Moultrie, played by Ejiofor.
Pic will start lensing Feb. 14 in Savannah, Ga.
Randall Miller and Jody Savin, who produced the 2008 indie feature “Bottle Shock,” will share producing credits via their banner Unclaimed Freight Prods. Duo partnered with John Cay and Meddin Studios’ Nick Gant and Jon Foster to close the “Savannah” deal.