The question of who is the tragic hero of Shakespeare's Julius Caesar has long been debated by literary scholars. For, both characters fit the profile of a tragic character--they possess noble character, hubris, a certain arrogance that blinds them to their shortcomings, their downfalls are not wholly deserved and, thus, effect a catharis, a feeling of pity and emotion, in the audience.
Caesar has proven his nobility in his many reforms made to Rome, his ability to form an all-weather army that could fight in any conditions, his conquering of Briton, etc. But, in his choice of going to the Senate because against the warnings of his wife and the soothsayer speaks to his hubris because he is going to be honored and because he proudly does not wish to be considered a coward:
Cowards die many times before their deaths;
The valiant never taste of death but once. (2.2.)
There is also a pity felt for Caesar (catharsis) as he is so brutally murdered, at least in part, by his friends "Et tu, Brute?"
These elements notwithstanding, there is the argument against Julius Caesar as a tragic hero since he is only present in the narrative of the play in three scenes (four if the ghost appearance is counted), The tragic hero should be the protagonist, the man character; Caesar is clearly not the main character. In addition, according the Aristotle's Poetics, the tragic fall is not pure loss. Before his death, the tragic hero experiences some gain in self-knowledge. So, while Brutus realizes his idealized decision has wrought more conflict for Rome than improvement, Caesar dies without any "discovery."
Although Julius Caesar does have some characteristics of a tragic hero, Brutus, not Caesar, is the tragic hero in Shakespeare's play.
According to Aristotle, a tragic hero is a person of noble birth who has a tragic flaw; he experiences a reversal of fortune, recognizes his faults, and takes responsibility for his actions. Though Julius Caesar was born into nobility, and though some might try to argue that his tragic flaw is ambition, he does not suffer the type of reversal of fortune Aristotle described in Poetics. Furthermore, he does not recognize his faults or take responsibility for his own downfall.