Gluck, as Handel and Vivaldi before him and all composers of his time, naturally recycled the "numbers" (arias and choruses) from older operas, rewriting the connecting recitative as necessary. In 1763 he reused nearly half of the 25 musical numbers from the Prague Ezio of 13 years earlier, avoiding material like "Se povero il ruscello" from the Prague Ezio which he had already used at the Vienna Burgtheater the previous year in the Vienna Orfeo as "Che puro ciel," and Gluck filled up the rest with 7 arias from Il trionfo di Clelia, which was also unknown to Viennese audiences. Recycling the arias from the Prague Ezio and Il trionfo di Clelia still required Gluck to transpose and adjust for the new singers, and reorchestrate for a bigger orchestra. Gluck also trimmed the opera by shortening the overture and cutting repeats. Ezio was sung by Gaetano Guadagni, Valentiniano by Giovanni Toschi, Massimo by Giuseppe Tibaldi, and Fulvia by Rosa Tibaldi.

Librettist Pietro Metastasio
Date of composition 1749 (revised in 1763)
Premiered 1750 in Prague, Czech Republic
Type Opera
Catalogue Wq. 15
Spoken language Italian
Instruments Voice (Castrato) - Alto ; Ezio, general
Voice (Castrato) - Soprano ; Valentiniano, emperor
Voice (Tenor) - Massimo, Roman patrician
Voice (Soprano) - Fulvia, Massimo’s daughter
Autotranslations beta Christoph Willibald Gluck: Ezio, Wq. 15
Christoph Willibald Gluck: Ezio, Wq. 15
Christoph Willibald Gluck: Ezio, Wq. 15