Old Major, a prize-winning boar, gathers the animals of the Manor Farm for a meeting in the big barn. He tells them of a dream he has had in which all animals live together with no human beings to oppress or control them. He tells the animals that they must work toward such a paradise and teaches them a song called “Beasts of England,” in which his dream vision is lyrically described. The animals greet Major’s vision with great enthusiasm. When he dies only three nights after the meeting, three younger pigs—Snowball, Napoleon, and Squealer—formulate his main principles into a philosophy called Animalism. Late one night, the animals manage to defeat the farmer Mr. Jones in a battle, running him off the land. They rename the property Animal Farm and dedicate themselves to achieving Major’s dream. The cart-horse Boxer devotes himself to the cause with particular zeal, committing his great strength to the prosperity of the farm and adopting as a personal maxim the affirmation “I will work harder.”

At first, Animal Farm prospers. Snowball works at teaching the animals to read, and Napoleon takes a group of young puppies to educate them in the principles of Animalism. When Mr. Jones reappears to take back his farm, the animals defeat him again, in what comes to be known as the Battle of the Cowshed, and take the farmer’s abandoned gun as a token of their victory. As time passes, however, Napoleon and Snowball increasingly quibble over the future of the farm, and they begin to struggle with each other for power and influence among the other animals. Snowball concocts a scheme to build an electricity-generating windmill, but Napoleon solidly opposes the plan. At the meeting to vote on whether to take up the project, Snowball gives a passionate speech. Although Napoleon gives only a brief retort, he then makes a strange noise, and nine attack dogs—the puppies that Napoleon had confiscated in order to “educate”—burst into the barn and chase Snowball from the farm.