The Mass of the Americas, a newly-commissioned Mass composed by Frank La Rocca, will premiere Saturday for the feast of the Immaculate Conception at the Cathedral of Saint Mary of the Assumption in San Francisco.

"The Mass of the Americas is a simultaneous tribute to Our Lady of the Immaculate Conception (the patroness of the United States) and Our Lady of Guadalupe (the patroness of both Mexico and all the Americas)," Archbishop Salvatore Cordileone of San Francisco has said. "It is in the high sacred music traditions of the Church, yet incorporates traditional Mexican folkloric hymns to Mary."

The Mass will be said Dec. 8 at 2 p.m. (PST), and will be televised and livestreamed by EWTN.

La Rocca is composer-in-residence at the Benedict XVI Institute, which was founded by Archbishop Cordileone in 2014 to provide practical resources to help parishes have more beautiful and reverent liturgies, and to promote a Catholic culture in the arts.

Archbishop Cordileone had requested the Mass, desiring a Mass setting that would reflect the multicultural diversity of the Church in the Americas.

The Mass of the Americas is a parody Mass, primarily using La Guadalupana, a Mexican folk song celebrating Our Lady of Guadalupe. It is written in Spanish, Latin, English, and Nahuatl – the Uto-Aztecan language in which Our Lady of Guadalupe addressed St. Juan Diego.

In an interview at the Benedict XVI Institute's website, La Rocca noted that he and Archbishop Cordileone "were both aware, in general terms, of the musical models used by missionary priests in Mexico, or later, California; they incorporated beloved popular tunes into the total experience of the Mass," and that the archbishop suggested the use of La Guadalupana.

"La Guadalupana has always been, and it sounds like, a typical Mexican Mariachi tune … The challenge before me was to make the tune recognizable enough so anyone paying attention would sit up and say, 'I know that' but stripped of the sombreros, the guitars, the crooning violins and of course the words," La Rocca said.

He noted that such a use of folk music in classical compositions is nothing new, and was actually a notable feature of German romanticism.

The Mass of the Americas is written for a 16-voice mixed chorus, along with organ, string quartet, bells, and marimba (a percussion instrument native to the Americas).

The Communion meditation is a Nahuatl setting of the Ave Maria which uses the marimba; La Rocca has said that "there are ways of getting the marimba to sound that are unfamiliar to most people, a way that will fit right in, and that's what I have done."

The Mass concludes with the Marian antiphon Alma Redemptoris Mater; following the singing of the antiphon, the organ continues with its tune, and the strings harmonize it with La Guadalupana.

Through its combination of sacred music traditions, folk music, and several languages, the Mass of the Americas "embodies the way Mary, our Mother, unites all of us as God's children," Archbishop Cordileone said.