All of the main characters died. The last scene takes place in the afterlife.Let's get serious for a moment, there's no chance in hell that the hunter guy survived getting stabbed in the throat by Naritsugus Wakisazhi and then slashed over the chest and stomach by a bad guy Samurai. Still, he comes running up to the main character in the end, perfectly healthy and showing no visible wounds except for a bit of dried blood. Certainly not nearly as badly injured as he should be. The main character has a dazed and confused expression on his face as well, as if he doesn't know where he is. Not very strange after a battle of that size, but the he's a warrior who has trained for stuff like that, and the other guy is a hunter who hasn't. Still he's more upbeat than the Samurai is. The strange comment about "travelling to America and sleeping with barbarian women" might be something which he's desired to do subconciously, and know when he's dead and nothing else matters, it's the first thing that comes to his mind. Diplomatic contact between Japan and the US didn't begin until the 1850's. The earlier scene where the Mooks are lauging maniacally and brutally beat each other to death with stones, is symbolic of them descending to hell for having served an evil lord. Note the reddish-dark colour in the scene.
Naritsugu was reincarnated 30 years after the events of the film in Imperial Germany.Okay, so let's consider a few facts about Naritsugu. Firstly, he seems like dressing entirely in white. Secondly, whilst he's nearly always calm and polite, he's an amoral, psychopath. Thirdly, over the course of film, he develops an interest in war. The logical conclusion of this? 30 years after his death at the hands of Shinzaemon, Lord Naritsugu is reincarnated in Imperial Germany, just as WW1 is getting going. A couple of decades later, he joins the Nazi Party, and more specifically the S.S., where he rises to the rank of Sturmbannführer - or, in English, Major. He then gets an order from Adolf Hitler himself to start work on creating artificial vampires, and, well... let's just say that, eventually, he gets all the war he could desire.