Central to the film is the exaltation of nature and its beauty. Throughout the film, the forest is described as magical and is shown to have healing properties throughout the film. In a scene from 24:01-28:00, Prince Ashitaka finds two wounded soldiers who are initially terrified of the forest that they had been conditioned into thinking was a dangerous land filled with vengeful spirits but are eventually calmed by its tranquility and beauty and are even alleviated of much of their pain. Animals in the film are not mere boars and wolves but towering godly representations of the animals in their tribe. The humans of Iron Town, however, want to strip the forest of its resources and leave it a bare site of economic exploitation. The town sticks out like a sore thumb, a brown industrial wasteland amidst a sea of green. The leader of Iron Town as well as the Emperor of Japan also want to kill the Forest Spirit, proving their dominance over nature. The Forest Spirit has the power to give life and beauty to the world, but it can also take all of that away. Humanity is at nature's whim, and we would do well to remember that.

The theme that comes secondary to nature is the theme of anti-war/violence. To see evidence of this film, look no further than the title Princess Mononoke which translates to Princess of the Vengeful Spirits. The boar demon that comes to Prince Ashitaka's village at the beginning of the film becomes a demon because he was shot and killed by the humans of Iron Town turning him into a vengeful spirit of hate. Prince Ashitaka's curse is also referred to as a "curse of hatred" and grows and festers during times of immense conflict (see the timestamp 50:48-51:05 in the film for a prime example). The Boar tribe in the film is also nearly wiped out and becomes more and more stupid as a result of their need for vengeance and violence. The Boar God in the film is quite literally blinded by rage, unable to see the destruction happening to his own tribe. Finally, the people of Iron Town are so concerned with wiping out the Forest and killing the gods that inhabit it that they ignore the violence happening in their own town as the Emperor comes to invade. Everywhere you look, there is some form of violence and a supremely negative consequence as a result.

This film contains not only themes of generalized anti war and violence but also allusions both obvious and subtle to colonialism and indigenous violence. For one, each animal god is the leader of their "tribe" (wolf tribe, boar tribe, ape tribe), and are attempting to defend their forest from human invaders that come equipped with guns and advanced weaponry. It is also no coincidence that the only human character in the forest wears red war paint and fights back with knives and bows. Prince Ashitaka also hails from the Emishi Tribe, a real life indigenous tribe in Japan that was wiped out by the emperor both in the film and in history. The Emperor exists throughout the film as an ever-encroaching colonial force. He wants to invade the forest and kill the forest spirit for immense power and wealth as well as take over Iron Town for the exact same reason. This forces Iron Town to grapple with their own colonial practices to avoid the same fate they bestow upon the forest.

Princess Mononoke depicts various facets of feminism in, I think, effective ways. Prince Ashitaka's Emishi tribe is matriarchal with the sage wise woman being the leader of the tribe. The Wolf God is also female and is both cunning and wonderfully brutal and powerful. Iron Town is also lead by a woman, Lady Eboshi. While she is violent and hate-filled, she also has sympathetic qualities including taking in women from Japanese brothels and giving them a better life. She represents an extremely complex female character that is often missing, especially in the fantasy genre. The women of Iron Town are feminist figures in their own right, representing Rosy the Riveter figures as they are the ones that work the iron bellows while the men are out exploiting the forest and keep the town running. They are the lifeblood of the town and defend it from attack on numerous occasions. San is also an example of a powerful female character in the film, someone who will not back down as her home is being invaded and destroyed.