Act 1, scene 1
Two gentlemen are talking in the palace of Cymbeline, King of Britain. The First Gentleman says that all the courtiers are frowning, reflecting the sorrowful mood of the King. He explains the reason: the King's daughter, Imogen, has married Posthumus Leonatus, a poor but worthy man, against the wishes of her father and his current wife, the Queen. The King has banished Posthumus and imprisoned Imogen. The King and Queen had wanted Imogen to marry Cloten, the Queen's son by a previous husband.
The First Gentleman says that despite their sad appearance, the courtiers are secretly glad about the marriage, as Cloten is "too bad for bad report" (line 17). In contrast, he says Imogen's chosen husband is both outwardly handsome and inwardly good. He is the son of Sicilius, who won military glory fighting for King Cymbeline's father, Tenantius, against the Romans. Sicilius earned the surname Leonatus (lion's whelp) for his bravery. Besides Posthumus, Sicilius also had two other sons, who died in battle, "with their swords in hand" (line 36), whereupon Sicilius died of grief. Sicilius' wife was pregnant and died giving birth to Posthumus.
Since Posthumus was now an orphan, the King took him under his care and brought him up. Posthumus grew to be loved and respected in the court. The First Gentleman says that his virtue is demonstrated by the fact that Imogen, the King's daughter and heir, has chosen him. Imogen is the King's only child. He once had two sons, but twenty years ago, both were stolen from the nursery when the eldest was three and the youngest a baby. The Second Gentleman is surprised that the King's children were so poorly guarded, and the search so slow that it could not trace them.
The gentlemen end their talk as the Queen, Posthumus, and Imogen enter.
Little is known about the historical Cymbeline, son of Theomantius (Shakespeare calls him Tenantius). He became King of Britain in 33 BC, when it was an outpost of the Roman empire. He reigned for 35 years, leaving two sons, Guiderius and Arvigarus. He was brought up in Rome and was absolved by Augustus Caesar of paying tribute. Subsequently, tribute was demanded and refused, but the chronicler Holinshed, one of Shakespeare's main sources, is unsure whether Cymbeline or some other King refused to pay. Caesar then invaded Britain. Holinshed wrote that British chroniclers claim the Romans were twice defeated in battle, but comments that Latin sources claimed ultimate victory for the Romans. Shakespeare, for the purposes of his play, has Cymbeline refuse to pay the tribute.
The play's first scene is an expository one in that it gives the background to the story and tells us something about the main characters. It sets up a stark contrast between Imogen's two suitors: the Queen's son Cloten, an unworthy man, and the King's ward, Posthumus, as virtuous as he is attractive.
It also introduces two major themes of the play. The first is outward appearance (the courtiers' sad faces) versus inward truth (their happiness at Imogen's marriage to Posthumus). At court, the two are at odds, leading to a hypocritical atmosphere. Related to this theme is outward nobility of birth (which Cloten has), which is not earned and which can be superficial, versus inward nobility of character (which Posthumus has), which must be earned and runs deep. Imogen, who is both well-born and appreciates true goodness, unites both. However, in her decision to marry the poor but worthy Posthumus, she has initiated a conflict with her parents, who are unable to see beyond his undistinguished birth.
The disappearance of the King's sons carries intense symbolic importance. The Romance tradition of literature often featured a king who was wounded or disabled in some way. When the king, the symbolic head of a nation, was sick, his country was sick too: crops failed, disease and famine thrived. The hero of the story went on a quest to find the regenerative "cure" for the king's ailment and, by extension, his country. In this tradition, to which all Shakespeare's Romance plays (A Winter's Tale, The Tempest, Pericles and Cymbeline) belong, the cure is often found by someone from the younger generation, which represents regeneration, fertility, and vigorous new life.
In Cymbeline, the fact that the King has lost his sons leaves him cut off from this life-giving quality. Only Imogen is left of the younger generation, but the King has rejected her. Severed from the regenerative root, the King and his court are left to wither and decay in destructive emotions like resentment and revenge. Through reference to the Romance tradition, we expect that Cymbeline's cure will involve being reunited with his sons and reconciled with Imogen.