Kurosawa always wanted to make a really entertaining film. The idea he had was so simple and interesting, it surprises me that no one else ever thought of it earlier! The idea was about rivalry on two sides, both sides being equally bad. We all encounter situations where we are stuck between two evils and are weakened by the situation. Exactly where Kurosawa made our protagonist different!
In Yojimbo, our protagonist is able to stand squarely between the two evils and end them both. The idea had an obvious element of humor. Kurosawa could have chosen to make his protagonist an idealist. It is interesting to think how an idealist protagonist in the same setup would have been, but considering Kurosawa’s affinity towards realism, it was too much to ask for. The protagonist is rueful, cynical, and amoral. For this reason Kurosawa refused several genres for the film- first tragedy, then melodrama. He instead, insisted upon making it a comedy. And hence the next decision of giving a western style and feel to the film over traditional Japanese styles he uses in his earlier films.
The townspeople of the film are essentially comical. They are a gallery of grotesques, a congress of monsters who seem to have popped out of a Charles Dickens novel. If you observe Kurosawa’s films carefully, this is a common trend. Watanabe in Ikiru, the doctor in Drunken Angel, the detective in Stray Dog, all seem to face the dilemma of being trapped in a world filled with evils. Our protagonist in Yojombo, suddenly has no dilemma. His only problem is have enough food to eat and find something interesting to do!