Lady Eboshi

"Watch closely everyone. I'm going to show you how to kill a god. A god of life and death.
 * —Eboshi, preparing to kill the Forest Spirit."

Lady Eboshi Gozen was the main antagonist of Princess Mononoke.She was portrayed by Yuko Tanaka in Japanese and Minnie Driver in English

In the film (spoilers).
Lady Eboshi's first scene when she with her army transportating rice to Irontown where they are attacked by San and the wolves but survive. When Ashitaka comes to Irontown he meets Eboshi Ashitaka learns that Eboshi is responsible for turning Nago into the demon. T hen San comes to Irontown to fight her. Later she attempts to kill the forest spirit and has her right arm bitten off by Moro, near to death she promises to rebuild a better town and leave the forest alone.

Appearance and personality.
Eboshi is a greedy woman who 'wants to rule the world'. As the leader of Irontown, the townspeople love her, giving her the highest praise and gratefulness. In pressing situations she's shown as calm and collected, attributing to her status as leader. She has a definite authoritative air about her, though behind there's a good deal of arrogance, which Ashitaka inevitably sees and provokes… She's also very a strong female who understands the injustice of the women's positions in society. Needlees to say, all of the women in the town have established the belief that men are all infidels. She has black hair that she ties up in some sort of traditional style, finishing off with a pink ribbon. She's the only female in the film who wears lipstick. She wears Hakama, a dark red male kimono, and a huge cloak that she hangs on her shoulders. This outfit is reminiscent of 'Shirabyoushi (prostitutes who danced in men's attire)' (-cited from nausicaa.net, Miyazaki interview), which hints at her backstory. It is never determined in the film, but she's said to have a very difficult past, which provokes her high opinion of herself, and her low opinion of others problems. When she's in her 'battle attire' she wears a shorter cloak, and a red 'eboshi cap' which gave her name. She has a very ambitious agenda, which is what drives the film, but in the end she is shown to be remorseful. While she's definitely the antagonist of the film, she's not exactly a typical villain; she gets a number of moments of praise. While she kills forest beasts and samurai, she also frees prostitutes from brothels, takes in lepers, and brings them all to her Iron Fortress. Admittedly, the girls work the forge and the lepers make guns for her making her a grey character.