Gratiano is Brabantio’s brother. He is one of the Venetians who arrive on Cyprus after Othello’s victory, in his case bringing the news of Brabantio’s death.
Walking home with Lodovico he comes across the wounded Cassio and is convinced by Iago of Bianca’s likely guilt in the matter. He is shocked that Iago would raise a weapon against a woman. He appears quite taken aback at the strange world he seems to have come into, and soon the most he can do is wish torture on Iago. As the last remaining relative of Othello’s wife, he inherits all of the Moor’s wealth.