Wikipedia
Sant'Alessio
Il Sant'Alessio (Saint Alexius) is an opera in three acts composed by Stefano Landi in 1631 with a libretto by Giulio Rospigliosi.
Sant'Alessio was the first opera to be written on a historical subject. It describes the inner life of fifth-century Saint Alexis. The work broke new ground with a psychological characterization of a type that was new to opera. It also contains interspersed comic scenes that are anachronistically drawn from the contemporary life of Rome in the 17th century.