Provide four examples from the text of Animal farm which describe Napoleon's character traits. Indicate whether each of the traits influences the...

In order to effectively complete this task, you obviously have to know what a character trait is. The term refers to the characteristics which make up a person's personality - these may be mostly good or bad or the character may be presented as a balanced character who is neither specifically good or bad.

Look for examples in the text which describe what kind of an animal Napoleon is. Chapter two, for example, provides a distinct contrast between Napoleon, Snowball, and Squealer. Focus on Napoleon's character description and how he differs from the other two specifically. You should then be able to closely define which character trait he does or does not have in this regard.

Look at what Napoleon does when he gets rid of Snowball. What does this particular incident suggest about him? Furthermore, look at his actions after Snowball's expulsion. How do these provide further insight into his character? You can also explore Napoleon's instructions to Squealer - what do these suggest about his personality? There are many relevant incidents you can explore in this instance such as the alteration of the commandments, Squealer talking about Napoleon's 'tactics' etc.

A good idea would also be to refer to how Napoleon treats the other animals, specifically his dogs, the sheep, the porkers that protested, the hens, his treatment of Boxer, and so on. The specific texts can be used to gauge which trait or traits Napoleon displays in these instances.

Further insight can be gained from Napoleon's relationship with the solicitor, Mr. Whymper, the fact that he played Frederick off against Pilkington, and , the issue regarding the fraudulent notes. Also, food for thought would be Napoleon's misrepresentation of the quantity of food on the farm. 

You can also describe Napoleon's character by interpreting which traits he displays when he starts walking on his hind legs, carries a whip, starts drinking, has his food tasted, have the dogs constantly surround him and so forth. All of these particular instances provide insight into his character.

Added to all of this, it will be easy to make a connection between the circumstances and conditions in which Napoleon does what he does in order to meet the requirements of the second part of your question. You will be able to determine whether it's the circumstances or setting which makes Napoleon act the way he does or whether his actions determine the circumstances, and the effect it has on the other animals.

I am quite sure that if you follow the guidelines I have mentioned, you will have more than enough material to successfully complete the task.