Said cast was mostly known, via a combination of news dribs and drabs and a well-received live reading of an earlier draft of the screenplay. According to a press release from TWC:
The Hateful Eight are: Academy Award nominee Samuel L. Jackson (DJANGO UNCHAINED) as Major Marquis Warren, Golden Globe nominee Kurt Russell (ESCAPE FROM NEW YORK) as John “The Hangman” Ruth, Golden Globe nominee Jennifer Jason Leigh (MRS. PARKER AND THE VICIOUS CIRCLE) as Daisy Domergue, Emmy nominee Walton Goggins (Justified) as Chris Mannix, Academy Award nominee Demian Bichir (A BETTER LIFE) as Bob, Academy Award nominee Tim Roth (RESERVOIR DOGS) as Oswaldo Mobray, Michael Madsen (RESERVOIR DOGS) as Joe Gage and Academy Award nominee Bruce Dern (NEBRASKA) General Sanford Smithers. Also, Channing Tatum (FOXCATCHER) has signed on for a role in the project.
That’s pretty much the same cast as the live read, with the exception of Leigh (who takes over for Amber Tamblyn) and Bachir (whose role was filled by Denis Ménochet).
The biggest news here for Tarantino fans is the reunion with Reservoir Dogs and Pulp Fiction co-star Roth; it’s the first time they’ve worked together since the ill-fated 1995 anthology film Four Rooms. In fact, much of the cast has worked with Tarantino before, as is his custom—and for those keeping track, this will mark his seventh collaboration with Samuel L. Jackson (counting Inglourious Basterds, where Jackson is heard but not seen, and True Romance, which Tarantino wrote but did not direct).