Napoleon the pig is named for Napoleon Buonaparte, a French military leader who became emperor of France in the early nineteenth century. However, Napoleon is modeled after Soviet dictator Joseph Stalin.

Because Orwell was writing fiction, he wanted to create strong and recognizable parallels to the Russian Revolution and how it went wrong, but not confuse anybody into thinking he was writing exact history. He wanted Napoleon the pig to be modeled after Stalin, not to be seen as an entirely exact depiction of Stalin. Therefore, he chose the name of another notorious dictator with global ambitions.

The Emperor Napoleon was noted in later life for being dictatorial. Like the pig named for him, the historical Napoleon was highly ambitious. Further, he went from being a supporter of the French Revolution, which established a republic based on idealistic notions, to an emperor, reestablishing a monarchy. Napoleon the pig parallels this move by first being (or pretending to be) a supporter of the revolution and of Animalism and, then, later, acting almost like an emperor. When he moves into a house, sleeps in a bed, wears clothes, and walks on two legs, he betrays the revolutionary principles of Animalism as surely as the historic Napoleon did the ideals of " liberty, equality, and fraternity" that were the basis of the French Revolution.

After running Snowball off the farm, Napoleon becomes the leader.  At the end of the book, Napoleon becomes a corrupted leader and, standing on two legs just like the formerly hated humans, reverts the name of the farm back to Manor Farm.

Napoleon was named after French military leader Napoleon Bonaparte.  Because of his rise to power and subsequent ruling styles, the name Napoleon has become synonymous with dictators and the idea the power can corrupt.  This is fitting in the case of Animal Farm where this Napoleon raises to power after making secret deals with neighbors and kills numerous friends who confess to chasing Snowball off the farm, when in fact it was he who drove off his former friend.