In Shakespeare's "Othello," Othello himself is clearly distinguished as the play's tragic hero, owing to his possession of what Aristotle termed a tragic flaw. A tragic flaw is broadly defined as a human vulnerability or moral weakness in an otherwise virtuous and upstanding character. In Othello's case, his main tragic flaw was his racial or cultural insecurity.
Being marked as an outsider within Venetian society on account of his Moorish (North African) heritage, Othello is often conscious of his behavior and speech. As he says in Act 1, Scene 2 of the play, he is "rude" in speech and "little blessed with the soft phrase of peace." He also remarks, in Act 1, Scene 3, that Desdemona's father was chiefly interested in Othello for his exotic tales. It is this weakness of insecurity that brings about Othello's downfall and which Iago manipulates. Already feeling outcast, it was clear that Othello was ready to victimize himself with only minimal encouragement from outside.
Othello is also described as a tragic hero on account of his overriding passions, which are linked to the perceived barbarism of his race. It is common in Shakespeare's plays to explore characters' innate passions by exploiting them with external factors.