On this date in 1785, a new Piano Concerto in C major was given its premiere at the Burgtheater in Vienna, with its composer, Wolfgang Mozart, at the keyboard. Years later this piano concerto was labeled as Mozart’s 21st, and given the number 467 in the chronological list of his works compiled by Ludwig, Ritter von Koechel, an Austrian botanist, mineralogist, and Mozart enthusiast. Today this work is popularly referred to as the “Elvira Madigan” Concerto, for the simple reason its romantic slow movement was used to great effect in a 1967 Swedish film of that name to underscore a passionate love story. That Swedish movie helped to bring Mozart’s concerto to the attention of a far wider audience than ever before, as did the 1984 movie “Amadeus,” with Mozart’s music in general. Musicologists may wince when they hear the title “Amadeus”–it’s a matter of historical record that Mozart signed his name “Amadeo” or “Amadé.” Others object that a Swedish film should provide a nickname for one of Mozart’s most sublime works–but, for better or worse, both “Amadeus” and “Elvira Madigan” are labels that seem to have stuck to Mozart’s name and his concerto.