Black people in Venice suffered from racial prejudice in Shakespeare's time, and this larger social context influences the plot of the play. Desdemona's father, Brabantio, for example, considers the marriage of his daughter to Othello with suspicion, as he thinks Desdemona "fear'd to look on" Othello's dark face. He has, therefore, to be reassured that Othello did not kidnap her and that she truly loves him.
Othello is insecure about his race—but at the start of the play he is able to behave rationally. He reasons that since "she had eyes, and chose me," his race must not matter greatly to her. However, once Iago starts playing on Othello's insecurities, his internalized racial self-loathing begins to overwhelm him. Iago suggests, for example, that "[Desdemona's] will, recoiling to her better judgment" might "repent" of marrying a black man.
Finally, using incessant lies, innuendos, and manipulations, Iago manages to convince Othello that Desdemona must find him unworthy and be sleeping...
(The entire section contains 2 answers and 606 words.)