In Shakespeare’s Twelfth Night, Orsino is the Duke of Illyria who is in love with Olivia. He begins the play absorbed in romantic longing and repeatedly sends his page Cesario to plead with Olivia on his behalf.
Orsino’s love is complicated by Viola, who has survived a shipwreck and disguises herself as Cesario. Viola falls in love with Orsino while delivering his messages, while Olivia falls in love with Cesario. The resulting triangle drives much of the play’s comedy and emotional tension.
Orsino is not a count, knight, or steward: he is the ruling duke of Illyria, the play’s fictional Adriatic setting. When Viola’s identity is revealed and the confusion over her twin Sebastian is resolved, Orsino abandons his pursuit of Olivia and agrees to marry Viola. Antonio is Sebastian’s friend, while Malvolio serves in Olivia’s household.