Motezuma's opening performance took place in 1733 in Venice, but sometime after that the work's score was lost. The libretto, by either Alvise Giusti or Girolamo Giusti, remained, and has apparently been performed since in a pasticcio by conductor Jean-Claude Malgoire.

The score was unearthed from the archives of Berlin's Sing-Akademie in 2002 by German musicologist Steffen Voss. Vivaldi experts have authenticated the manuscript.

Michael Talbot, a music professor and author, said, "Yes, it is real. Some of the material is common to authenticated works, like arias used in earlier operas. The stylistic parameters are also familiar. Beyond all doubt this is real."

Vlaardingerbroek said, "This is the most important Vivaldi discovery in 75 years."

Motezuma (the spelling is a variation on the more common "Montezuma") is a love story between Teutile, the daughter of the Aztec emperor, and Ramiro, brother of Hernšn Cort_s, conqueror of the Aztecs. Because the score is incomplete, the opera begins with the eighth scene.

A fully staged production of the opera will be peformed at the Barga Opera Festival in Italy this July, and at the Alstadtherbst in D‹sseldorf in September. Sardelli will conduct these performances, as well as another concert performance in Ambronay, France, in October.