It's certainly the first mainstream game, anyway; all of the previous ones to my knowledge was niche stuff on pre-PS2 consoles (i.e. KOEI back before the infamous Dynasty Warriors franchise once did a turn-based strategy game for DOS/SNES/Genesis called Liberty or Death) or on PC, and even then they're almost always strategy games, so this will most likely also be the first American/French Revolution-era "action" game.
Re: zee tension is stupendous