Understanding the historical context of Animal Farm and Orwell's political beliefs is essential to answer this question properly.
eNotes has many great resources to help you on this journey. I've attached links to get your started. One's a link to three essays on Orwell and the novel and I believe all three would be of use to you here. I've also provided the link to the analysis on Napolean, which outlines Orwell's intentions for him and the historical figures/ideals he's supposed to represent.
A hint: When an author uses a character to represent an ideal, the way he treats that character (relationship with other characters, the character's ultimate fate, etc.) are usually ways that the author shows us how he feels about that ideal.
Please look at the link on the historical context, too. It will really help put some things into perspective for you.
Good luck with it!