Ah, no no no, when I said historically, I meant that once viewing their history they were varied, not that per period they differed. I gotta learn to word things better, lol.
In any case, the ranger actually works wonders as a samurai class. Monk would definitely work well, especially if you were talking the more courtly samurai, wherein swashbuckler would also probably serve you well. No iaijutsu master cuts, but then again, all anime samurai could be insta-crafted from ToB, so we'll get creative. Fighter really does the job if you think about it, representing specialized training and more war-like skills. Slap Able learner on a human samurai, which is fine to use since fighters have damned enough feats as is, and they can net some social skills with their extra human skill points and such. Iono about spear/polearm related feats, but I'd assume you could easy-craft a warrior with them. Uber-katana skillz could just be Weapon Mastery, as friggin obnoxious long a list of reqs as it has.
Damnit, now I wanna make a samurai again, heh. In ways, barbarian could work, but not as a staple; some were very emotionally driven, and relied on heavier offensive tactics to constantly threaten an opponent, thus keeping said foe on the defensive until (the law of probability kicks in, heh) eventually their opponent, unable to attack back, was slain. But you'd still need some sort of class to show specialized training with the weapon, which Kensai does in a way. Does the samurai have allegiance to a family, individual, political group, military organization, they get a little complicated, but all can be pretty easily created. Basically, get mucho detail on their role aspect, then we'll work on crafting the numbers (odd as it is to say that onn the CO boards....)