Actually the main director, producer, and creator of the show, is Bruno Heller, who I happened to have known some years back. A terrific writer. Not quite David Chase, but then, who is??
Well-regarded Right Wing renegade director John Millius (Magnum Force, Red Dawn, Conan the Barbarian) is an exec producer who also wrote a few eps. His fingerprints are all over this show. Awesome.