"not much of a talker, but with a reputation for getting his own way."
Snowball seems a more complex character. Orwell wrote:
"Snowball was a more vivacious pig than Napoleon, quicker in speech and more inventive."
It seems as though Orwell wanted to say that revolution leaders used more forceful tactics than other possible candidates that were altogether more sensitive, resourceful and intelligent. One such example is Napoleon's ignorance towards Snowball when he urinated on his blueprints for the windmill. He also used force to brainwash the sheep into saying one phrase exactly when he wanted them to.
Although Napoleon was written to represent Stalin, his character also focuses our minds on all dictators such as Hitler, Mussolini or Castro. Napoleon represents a communist dictator such as Stalin or Castro, Hitler and Mussolini were fascists and supposedly hated communism however their regimes were in fact very similar totalitarian systems.
Napoleon is the only character that changes very slightly. He becomes more and more corrupt such as buying alcohol and changing commandments. The reasons for these changes are not given by Napoleon but explained by Squealer the propaganda machine.
Boxer is an enormously strong horse upon which the survival of the farm depends. He is exploited first by Mr Jones and then by the pigs as he puts in the most effort and in return receives no extra benefits. Boxer represents the ordinary, decent worker; it could be argued that his character is essential to any kind of social system. Boxer's favourite phrases "I will work harder," and "Napoleon is always right," are used by Boxer to answer almost any question. Unfortunately Boxer was so devoted to Animal Farm he never understood the whole system was corrupt. Boxer's attitude towards inflicting harm upon others changed dramatically. At first he would never use his great strength the hurt or harm any living creature. During the battle of the cowshed he thought he had killed a stable boy. He is described as having "tears in his eyes" and admits he never meant to kill him. However later in the book when the dogs launch an attack on Boxer, he pins one down and was ready to kill it unless Napoleon intervened. I think this could show he had begun to lose his faith in the revolution even though he still listened intently to Napoleon.
Benjamin was Boxers companion. He is the only animal to doubt the ability and honesty of the pigs. Benjamin could read very well but he refuses to put this skill to use. Only at the end of the book, after Boxer's death does Benjamin agree to read out the final Commandment. Benjamin can be seen as the wasted intellectual who refuses to achieve anything, as he knows it is pointless under the strict Animalist regime. Clover is a motherly figure on the farm. Her character complements Boxer's qualities of strength and hard working.
Mr Jones had fallen on hard times (in a similar way to Tsar Nicholas II of Russia) I don't think this would give his character an excuse to neglect and be brutal with the other animals. Orwell made him a fairly developed character but he is still just a stereotype.
Pilkington and Frederick represent different types of man but also different nations. Pilkington is gentle but his farm is badly managed as he spends his time shooting and fishing. He neglects his livestock but not intentionally. Frederick is more efficient but cruel towards his animals. Frederick is linked to Germany and Hitler, while his farm Pinchfield is a referral to Hitler's plans to expand Germany.
Pilkington represents France and Britain. Napoleon sides with one then the other - like Stalin's peace treaties with Nazi Germany and then the Western Allies.