Shakespeare's Cymbeline is one of his latest plays. Built around the narrative of King Cymbeline's battle against the Romans and his daughter Imogen's love for the heroic Posthumus Leonatus, the play is a complicated tale of betrayal and mistaken identity. Shakespeare derived the narrative of Cymbeline from historical texts such as Holinshed's Chronicles and Geoffrey of Monmouth's History of the Kings of Britain. Other elements of the play originate with the Decameron, by Italian author Giovanni Boccaccio.
Cunobelinus, a historical British king who ruled in what is today southeastern England in the late first century BC and early first century AD, is the original inspiration for the character of Cymbeline. Although a powerful ruler, he was far from being king of all of Britain. His rule is known from the works of Roman historians, as well as from archaeological evidence.
Shakespeare's version of the character is based on the work of 12th-century historian Geoffrey of Monmouth. Monmouth's History of the Kings of Britain depicts Cymbeline as a great king and warrior, a leader who was both on friendly terms with Rome and capable of resisting Roman aggression when needed. The king's two sons, Guiderius and Arviragus, also appear in Monmouth's story.
The conflict between Britons and Romans is only part of the plot of Shakespeare's play. Much of the action centers on the relationship between Cymbeline's daughter Imogen and her lover Posthumus Leonatus. The couple are opposed by the queen, her foolish son Cloten and the devious Iachimo, who persuades Leonatus that Imogen has been unfaithful to him, causing him to flee the court and her to pursue him in disguise.
Iachimo manages to fool Leonatus by discovering that Imogen has a mole, a fact he could only learn by seeing her naked. Leonatus comes to the conclusion that Iachimo and Imogen have been lovers, but in fact the villain has discovered this by concealing himself in a trunk in Imogen's chamber and emerging while she is asleep. This scene is heavily inspired by a similar incident in the Decameron, a 14th-century Italian work by Boccaccio.
The structure of Cymbeline is highly complex, with several different plots relating to disguise and mistaken identity. It also incorporates elements unusual in Shakespeare's work, including a dream sequence in which the god Jupiter descends to earth riding an eagle. Many scholars have suggested that Shakespeare was experimenting with new elements that were becoming more common in Jacobean drama. This experimentation was to bear fruit in his next and last plays, The Winter's Tale and The Tempest.