Overview
Iago is a fictional character in Shakespeare's Othello (c. 1601–1604). Iago is the play's main antagonist, and Othello's standard-bearer. He is the husband of Emilia, who is in turn the attendant of Othello's wife Desdemona. Iago hates Othello and devises a plan to destroy him by making him believe that Desdemona is having an affair with his lieutenant, Michael Cassio.
The role is thought to have been first played by Robert Armin, who typically played intelligent clown roles like Touchstone in As You Like It and Feste in Twelfth Night.
Role in the play
Iago is a soldier who has fought beside Othello for several years, and has become his trusted advisor. At the beginning of the play, Iago claims to have been unfairly passed over for promotion to the rank of Othello's lieutenant in favour of Michael Cassio. Iago plots to manipulate Othello into demoting Cassio, and thereafter to bring about the downfall of Othello himself and also others in the play who trusted Iago. He has an ally, Roderigo, who assists him in his plans in the mistaken belief that after Othello is gone, Iago will help Roderigo earn the affection of Othello's wife, Desdemona. After Iago engineers a drunken brawl to ensure Cassio's demotion (in Act 2), he sets to work on his second scheme: leading Othello to believe that Desdemona is having an affair with Cassio. This plan occupies the final three acts of the play.
He manipulates his wife Emilia, Desdemona's lady-in-waiting, into taking from Desdemona a handkerchief that Othello had given her; he then tells Othello that he had seen it in Cassio's possession. Once Othello flies into a jealous rage, Iago tells him to hide and look on while he (Iago) talks to Cassio. Iago then leads Othello to believe that a bawdy conversation about Cassio's mistress, Bianca, is in fact about Desdemona. Mad with jealousy, Othello orders Iago to kill Cassio, promising to make him lieutenant in return. Iago then engineers a fight between Cassio and Roderigo in which the latter is killed (by Iago himself, double-crossing his ally), but the former merely wounded.
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