The first recorded mention of Othello is found in a Revels account indicating the play was performed at Whitehall Palace on November 1, 1604, but the play is believed to have been written in 1603.

Brabantio is a Venetian senator and Desdemona's father. He has entertained Othello in his home countless times before the play opens, giving Othello and Desdemona opportunity to fall in love.

Othello explains to the Duke of Venice and various senators that Desdemona became enamored of him for the sad and compelling stories he told of his life before Venice.

Cassio is a young and handsome lieutenant under Othello's command who becomes one of Iago's several victims in a plot to ruin Othello.

Iago persuades Roderigo to assassinate Cassio, and together they arrange an ambush. Roderigo attacks Cassio by surprise. Cassio retaliates and mortally wounds Roderigo, but is himself stabbed from behind by Iago. His leg is wounded, but he survives. Iago then kills the wounded Roderigo.

In Act IV, scene iii, as Desdemona is preparing for bed, afraid that Othello is wrongly angry with her for being unfaithful, she sings "The Willow Song", a mournful folk ballad, in which a lady laments her lost love.

Feeling betrayed by his daughter's elopement, Brabantio warns that she may betray her new husband as well.

When Othello arrives in Cyprus, he discovers that a storm has already destroyed the Turkish fleet.

When Desdemona's handkerchief shows up in Cassio's possession, Othello is convinced that his wife is unfaithful.

Iago says that he hates Othello for promoting Cassio, a younger and less capable soldier, above him.