Why has Orwell used animals as the principal characters?
In the tradition of such great satirists as Voltaire and Swift, George Orwell has written an allegory as the medium of his pointed criticism of Soviet Russia and Communism. The animals used as characters represent various people and types; by using these animals, Orwell depicts concepts in an easily identifiable way. As explanation, Orwell himself wrote that he attempted in his novel "to fuse political purpose and artistic purpose into one whole."
In the preface to his novella, Animal Farm, Orwell, who was a socialist, describes how the idea of setting the book on a farm came to him:
...I saw a little boy, perhaps ten years old, driving a huge carthorse along a narrow path, whipping it whenever it tried to turn. It struck me that if only such animals became aware of their strength we should have no power over them, and that men exploit animals in much the same way as the rich exploit the proletariat.
"Snowball was in league with Jones from the very start! He was Jones's secret agent all the time....Did we not see for ourselves how he attempted--fortunately without success--to et us defeated and destroyed at the Battle of the Cowshed?"