Wikipedia
Demofoonte is a dramma per musica or opera in 3 acts by composer Christoph Willibald Gluck. The work uses an Italian language libretto by Pietro Metastasio. The opera premiered on 6 January 1743 at the Teatro Regio Ducal in Milan.
Demofoonte is an opera in three acts by the Czech composer Josef Mysliveček. It was the composer's first setting of this popular libretto by Metastasio first produced in 1733 (it was common in the second half of the eighteenth-century for composers to set Metastasian texts two or more times over). This setting stays remarkably close to the original drama for its day (it was customary to alter Metastasian texts considerably so long after their original performances), but the role of Timante was augmented in order to highlight the talents of its interpreter, the distinguished male soprano Gaetano Guadagni. All of Mysliveček's operas are of the serious type in Italian referred to as opera seria.