Ciro in Babilonia, ossia La caduta di Baldassare is an azione sacra in two acts by Gioachino Rossini with a libretto by Francesco Aventi. It was first performed at the Teatro Comunale in Ferrara during Lent, 1812. The exact date of the premiere is unknown but is believed to be 14 March. During Lent it was the custom for Italian opera houses either to close or to stage works on themes from the Bible. Ciro in Babilonia is one of two Lenten operas by Rossini and is based on the Biblical story of the overthrow of the Babylonian king Belshazzar by the Persian ruler Cyrus the Great.

Ewa Maria Podleś was a Polish coloratura contralto singer who had an active international career both on the opera stage and in recital. She was known for the agility of her voice and a vocal range which spanned more than three octaves. She excelled in Rossini roles such as Rosina in Il barbiere di Siviglia, the title role of La Cenerentola, Isabella in L'italiana in Algeri and the title role of Tancredi. She was able to perform roles that Handel had written for castratos, such as Rinaldo and Giulio Cesare. Podleś appeared on leading stages of the world and made many recordings.