SAN FRANCISCO, Calif.—A lost piece by Wolfgang Amadeus Mozart was performed for the first time on the West Coast in a San Francisco library on Sep. 28.

About 70 people filled the Golden Gate Valley Library’s hall to hear the recently rediscovered “Serenade in C” for the first time.

Many of those in attendance stood while listening.

“Mozart’s music is the most famous there is, and it’s been performed millions of times all over the world, but not this piece,” Dan Flanagan, the violinist of the trio, told The Epoch Times.

“My jaw dropped, and my eyes opened wide. My first thought was, when do I get to hear it? When do I get to play it? Where’s the music?” Flanagan told The Epoch Times, describing his first thoughts after hearing about the music’s rediscovery.

“It’s not going to be the ‘Magic Flute’ that you know, but it is a precocious child prodigy’s masterpiece, for sure,” Flanagan told the audience before playing the 12-minute piece of music.

An audience watches as musicians play Wolfgang Amadeus Mozart’s "Serenade in C" in the Golden Gate Valley Libary, San Francisco, Calif., on Sept. 28, 2024. (Lear Zhou/The Epoch Times)

Now officially renamed “Ganz kleine Nachtmusik” in the “Köchel” catalog, the official bibliography of Mozart’s compositions, the work was believed to have been written by the Austrian composer when he was about 13 years old.

According to Flanagan, the seven chapters were composed just a few years after Leopold Mozart, young Mozart’s dad, brought him touring Europe to “show him off. “

Flanagan finally found the music sheet online on Sep. 23. Although they tried very hard to be the first performance in the United States, they were beaten by a trio at Penn Station in New York City.

Dan Flanagan, Karen Shinozaki Sor, and Victoria Ehrlich stand after playing Wolfgang Amadeus Mozart’s "Serenade in C" in the Golden Gate Valley Libary, San Francisco, Calif., on Sept. 28, 2024. (Lear Zhou/The Epoch Times)

A long-lasting warm applause following the performance showed the audience’s appreciation.

“It’s so cheerful, it’s so upbeat, even a Taylor Swift Fan would get that,” Sally Carlson, an 83-year-old Mozart lover, told The Epoch Times, talking about her favorite chapter “IV Polonese”.

“How wonderful to watch the interplay of the three musicians, they were really, very, very aware of each other,” she added.

Karen Shinozaki Sor plays the second violin, and Victoria Ehrlich plays cello in this trio.

The world premiere was on Sep. 19, in Salzburg, Austria, when the new catalog was unveiled. In North America, the honor belongs to Ottawa, Canada, on Sep. 27, according to a press release from the San Francisco Public Library.

This article has been updated to correctly reflect that the performance was only the West Coast premiere.