Marriage plays a pivotal role in progressing the plot of Shakespeare's Othello. We meet the protagonist and tragic hero, Othello, shortly after his marriage to Desdemona. The marriage of these two characters serves as the opportunity for Iago, the main antagonist, to plot Othello's downfall.
Iago dislikes our tragic hero because Othello has received a military promotion that Iago had his eye on. However, Iago is only able to enact his plan of revenge by enlisting the help of Roderigo, a man deeply in love with Othello's new bride. Iago uses Roderigo's passion for Desdemona to convince him to ruin Othello, promising Roderigo that by breaking up the newlyweds, he would have a chance of marrying Desdemona himself.
The first plan that Iago sets in motion, with Roderigo's help, is alerting Desdemona's father, Brabantio, that his daughter has eloped with Othello. Though Othello was received with honor to Brabantio's house, the senator is outraged that his daughter has eloped without his consent. He takes the matter before the Duke of Venice, and tries to convince the ruler that Othello has bewitched Desdemona into falling in love with him and the marriage should be dissolved. However, Othello and Desdemona effectively convince the duke of their love and together they leave for Cypress and Othello's new military assignment. As the couple is leaving, Brabantio warns Othello that because Desdemona has deceived her father, her husband should be on his guard as well, saying "Look to her, Moor, if thou hast eyes to see. / She has deceived her father, and may thee" (1.3.333-334). This warning serves as the basis for Iago and Roderigo's new plan to ruin Othello.
Once in Cypress, Iago and Roderigo plan to convince Othello that Desdemona is unfaithful and is carrying on an affair with Othello's best friend and right hand man, Cassio.
Interestingly enough, the "proof" that Iago needs to convince Othello that Desdemona has been unfaithful comes to him by his own marriage to Desdemona's friend and servant, Emilia. While cleaning, Emilia finds a handkerchief that Othello gave Desdemona as a token of his affection. Trusting her husband, Emilia gives it to Iago, who then places it in Cassio's room. When Othello finds out that the treasured token he gave his wife was found in another man's room, he is convinced of her infidelity and he descends into a downward spiral that eventually claims his life as well as Desdemona's. He decides to smother his wife in her sleep for her unfaithfulness, but is interrupted by Emilia. With her dying breath, Desdemona refuses to tell Emilia that her husband was responsible, proving her loyalty and devotion to her husband and their marriage. When Emilia realizes what has happened, and her own husband's part in the couple's downfall, she turns Iago in and he is eventually punished for his crimes.
Both marriages end tragically, though one was true and loyal and the other deceitful and false.
In Othello, marriage plays a significant role in uncovering the characters' development of identity. For example, Othello feels very lucky to have Desdemona as his wife because he harbors an inner sense of inferiority based on his race. Although he is respected as a leader, he is aware that people do not want to necessarily welcome him as part of the family. Desdemona loves Othello for who he is, and she does not play into the negative stereotypes that others have about black people. The marriage for her is a way to publicly state that her love does not know any boundaries--she is proud to be married to Othello and is willing even to risk her relationships with her father Brabantio to be with Othello. Iago knows this about Othello, and he uses Othello's weakness to prey on him. So, marriage in the play has direct ties to the characters' development of identity.