Brabantio is Desdemona's father. A Venetian senator, he is a magnifico, a prominent citizen and landowner in Venice. He charges Othello with bewitching his daughter and dies after Desdemona leaves for Cyprus with Othello and the Venetian forces.

When the play opens, Brabantio's household is being disrupted by Iago and Roderigo, who are crying out to Brabantio that he has been robbed. Brabantio says, "What tell'st thou me of robbing? This is Venice; / My house is not a grange" (I.i.105-06). He believes he is safely within the civilized society of Venice, not on the dangerous and uncivilized fringe of that society. When Iago cries that Brabantio's daughter is at that moment sleeping with the Moor Othello, he appeals to Brabantio's racial prejudices. When Brabantio recognizes Roderigo, he reminds him that he has prohibited Roderigo from pursuing Desdemona as a suitor. Moments later, Brabantio first reveals his racial prejudice when he tells Roderigo, ''O would you had had her! / Some one way, some another" (I.i.175-76). He would prefer anyone to Othello as his daughter's husband, even the unsavory Roderigo.

Brabantio cannot believe Desdemona has freely selected Othello. When Roderigo escorts him to the place where Othello is, Brabantio draws his sword and is ready to fight with the Moor. He accuses Othello of having used spells and charms to seduce and steal his daughter. He makes the same claim to the Venetian senate, arguing that Othello has certainly used witchcraft to win his daughter. In Brabantio's eyes, Desdemona is a maiden so modest that it is unthinkable for her "To fall in love with what she fear'd to look on!" (I.iii.98). When Othello explains that Desdemona was initially fascinated by Othello's tales of exotic adventures, eventually falling in love with him, Brabantio misses the irony. He shared that fascination himself, inviting Othello into his home so that Othello might entertain Brabantio and his guests with the tales of his daring exploits. When Brabantio hears Desdemona support Othello's story, he gives up his appeal. He never sanctions the marriage of his daughter to Othello and leaves uttering his total disapproval.