In Shakespeare's Julius Caesar, the two conspirators Cassius and Brutus have drastically different reasons for planning to kill Caesar.
Cassius's main reason for planning Caesar's murder is his envy of Caesar's power. Cassius believes that he is just as fit, if not more so, to rule Rome, and his desire to kill Caesar stems from this belief. At one point of the play, Cassius recalls a time during childhood in which Caesar nearly drowned in the river and Cassius saved him. Cassius pays specific attention to the image of Rome's mighty leader drowning amongst the torrents, and he cites bitter anguish at his political power:
And this man
Is now become a god, and Cassius is
A wretched creature and must bend his body,
If Caesar carelessly but nod on him.
Brutus's main reason for killing Caesar is his own undying love for Rome. He becomes entirely torn between these two loves but is ultimately convinced by Cassius that Rome is the more important of the two. His reluctance to betray his closest friend is slowly worn away.
Both of these two men die shortly after killing Caesar, as the assassination sets forth an onslaught of violence.