Old Major is the leader of the animals and the founder of animalism. He wrote spoke to his fellow animals about his plan for the future of animals. The animals loved the idea of them being equal and not being controlled by humans so they took on this idea and made it a reality.
Snowball gets chased out of the farm
The Battle of the cow shed was the first big move of the rebellion . It was the eye opener to what they thought was going to happen to them.So they fought against the humans with all their might
Pigs become humans
After the humans were gone they immediately started to work on the farm with the 2 contradicting leaders, Snowball and Napoleon.
Realization of Dictators
Napoleon used his malicious of puppies to chase out his enemy/partner away from the farm and to become the only leader of the farm.
The pigs that were left changed the seven comandments for their benefit. They slowly became humans themselves and dictators. The animals lack of education was a big reason to why they didn't know sooner.