The themes of Cymbeline are similar to those of the other Romance plays, The Tempest, The Winter's Tale, and Pericles.
Appearance versus reality
In Cymbeline, nothing is as it seems. Outward appearance does not fit inward reality. The courtiers are outwardly concerned but inwardly delighted at the Posthumus/Imogen marriage. The King does not really rule because he gives his power to the Queen. The Queen pretends to be on Imogen's side but works against her. Cloten is outwardly noble but inwardly ignoble. The Queen claims to heal but wishes to poison. Cornelius pretends to give her poisons but really gives her harmless opiates. Iachimo's story about Imogen is false, though Posthumus takes it for truth. Imogen disguises herself as Fidele. The king's lost sons do not know who they are. And so it goes on. The resolutions of the final scene are concerned with restoring truth, and marrying the outward appearance with the inward reality.
Youth and age
Cymbeline and, by extension, his court and the kingdom, has lost touch with youth and all that goes with it-love, fertility, and renewal. This is shown in the loss of his two sons, in his wedding a cruel Queen, and in his harsh imprisonment of Imogen. In contrast, the young Imogen and Posthumus act out of love. A parallel though less extreme situation exists in Belarius's household, where the courage and spontaneity of the boys contrasts with Belarius's caution. The play's resolution consists in a reunion of the younger with the older generation.
Restorative power of nature
Cymbeline is one of several plays in which Shakespeare contrasts the corrupt and decaying court with the purity and truth of the natural world. Cymbeline's sons are brought up in the womb-like world of the Welsh mountains, and Belarius leaves us in no doubt that this is a place where only truth thrives, where dissembling is stripped away. Here, Imogen finds unconditional love and reunion with her lost brothers. She "dies" only to awaken and find a corpse which she believes to be Posthumus's. Posthumus did not, in fact, die, but his old self has died in that he has repented. Thus the experience is a rebirth for Imogen. The natural theme is reinforced by imagery of birds, animals, flowers and trees.
Forgiveness and reconciliation
The final scene is characterized by forgiveness and reconciliation. Posthumus learns that Imogen was innocent and expresses repentance. Imogen forgives Posthumus. Cymbeline is reunited with Imogen and with his lost sons, forgives Belarius, and is reconciled with the enemy he vanquished. Iachimo repents and Posthumus spares his life. The King's acceptance of the Imogen/Posthumus marriage is a sign of individual peace and social integration.
There are, however, qualifications. The Queen, beyond redemption, died unrepentant and is unforgiven. Cloten never became worthy of forgiveness and died without having reached any degree of self-knowledge. And despite the sincerity of Iachimo's repentance, Posthumus only forgives him with the proviso that leaving him alive will be more malicious than killing him.