Charles Rosen, in his splendid study The Classical Style, considers this Concerto, which Mozart completed in January 1777, as the first truly mature masterpiece in Mozart’s oeuvre. Certainly it represents an astonishing advance over the handful of earlier original piano concertos in his output. In a letter to his father after finishing the piece, Mozart referred to it as having been written for someone named “Jenomy” and his father referred to her as “Madame Genomai.” Early in the twentieth century, two French scholars—unable to find further information about her—decided that the name was Mozart’s misspelling of Jeunehomme and that she must have been a traveling virtuoso—yet one of whom no one had ever heard. This name was copied uncritically throughout most of the century.

Michael Lorenz, a Viennese musicologist, discovered the answer to this vexing mystery in 2003. Mozart clearly met the pianist in question on Salzburg in 1777 when he wrote the Concerto for her. The following year, from Paris, he wrote to his father about meeting with the choreography Jean Georges Noverre, with whom he was planning a ballet, adding “Madame Jenomé is here as well.” The title “Madame” indicates that “Jenomé” is the lady’s married name (so she was not Mademoiselle Jeunehomme). She was in fact Noverre’s daughter, named Louise Victoire, a fine amateur pianist. In 1768 she married Joseph Jenamy, a wealthy merchant in Vienna. So instead of having found inspiration for his breakout work in the person of a completely unknown traveling virtuoso, Mozart found it within the family of a professional colleague with whom he proposed collaborating.

Mozart, just turned twenty-one, was a mature master of the utmost perfection. Perhaps there was something in Madame Jenamy’s playing or personality that inspired him to this new artistic level. Mozart himself played the Concerto several times over the years, suggesting that he, too, rated it highly among his works.

The Concerto feels big and spacious, though in fact it has only a very modest scoring. But with these small forces, Mozart accomplishes wonders of invention. The biggest surprise comes right at the beginning, and it is one that was so unexpected that Mozart could never have done it again in a later work without making it obvious he was repeating himself. The concerto style of the day called for the orchestra to play a lengthy ritornello, laying out many of the main themes, before the soloist ever sounded a note alone. In modern discussion of concertos, this is often referred to as the “first exposition,” though the term “ritornello” better implies its structural function, as an orchestral introduction consciously set out to prepare the arrival of the soloist.

But here, after the orchestra opens with a conventional fanfare figure, the piano leaps in at once with a saucy retort. This is only the first of many occasions in this Concerto in which the piano plays at unexpected times. Mozart is here creating a personality for his soloist, almost as if the Concerto were an elaborate operatic scene in which the soloist happens to be an instrument rather than a singer, but nonetheless has a genuine character all its own. One way in which the piano takes on a specific character is in the way Mozart lays out his lavish abundance of musical ideas in the first movement, in such a way that some are restricted to the piano alone, thus differentiating it from the orchestra. The freshness with which the movement proceeds—in that one is never quite sure who will play when—is part of the subtle wit that enriches the entire score.

The comparison with opera is by no means far-fetched, as the second movement makes entirely clear. This is quite literally a scena from some tragic opera, with muted strings and contrapuntal imitation between the violins to set the stage for the “singer’s” entrance. The gestures of C minor—dark, filled with pathos—all but overwhelm the gentler music in E-flat during the course of this impassioned aria.

The finale returns to the open-hearted wit of the first movement, to which is added the adventure of virtuosity, including reams of trills. Yet there are great surprises here, too, including a swoop into a graceful minuet—in a different tempo and key from the foregoing. A cadenza closes in the final brilliant section of the Presto. —© Steven Ledbetter