Mozart completed this work on February 10, 1785, and played the first performance the next evening in Vienna. Scoring adds a flute and two trumpets to winds, horns, timpani, and strings.

On February 11, 1785, Leopold Mozart arrived in Vienna after a wintry, bone-rattling, coach journey from Salzburg -- his first visit to the capital in 12 years and his last. On the same night he attended an Akademie by his celebrated son, who had just turned 29 and was at the peak of his popularity in ever-fickle Vienna. Leopold wrote to daughter Nannerl that, in the Casino on the Mehlgrube, he beheld "a vast concourse of people of rank.... The concert was incomparable, the orchestra excellent." After two arias by a singer from the Italian opera, there "came a new, superb piano concerto by Wolfgang, which the copyist was still writing when we arrived, and the rondo of which your brother hadn't time to play because he had to revise copies ." This was the trailblazing D minor Concerto that survived the neglect of so much of Mozart's music during the nineteenth century. Beethoven, both smitten and influenced, played it publicly, with his own cadenzas in the first and last movements, where Mozart had improvised. No reports have survived of the audience's acceptance, but had they been hostile or even cool, surely Leopold would have reported this to Nannerl. His son's marriage without paternal permission in 1782 to Constanze Weber still rankled; so did their newfound independence. However, Papa's immediate and unreserved acceptance of Wolfgang's departures from tradition in the new concerto -- beginning immediately with an agitated, subtly changing bass line beneath the throbbing syncopation of violins and violas -- revealed a flexibility otherwise missing in his personal character. One can almost admire the manipulative Leopold for that.

In the first movement, Allegro (D minor, common time), Mozart's themes are motivic rather than conventionally melodic; more than two centuries later it remains a miracle that the soloist never plays exactly what the orchestra sets forth in the exposition, despite a rock-solid sonata structure throughout. When the piano finally enters in measure 77, it does so as an alien in a threateningly troubled land. Nor does the soloist take complete charge until the coda of the finale where, half-an-hour later, he coaxes the music into D major.

The second movement is a Romanza (B flat major, common time). Not to underrate Mozart's incomparable genius in music before this, nothing had equaled the unity of expression achieved in 1785 and after. Beyond integrating the outer movements, he made the slow movement part and parcel of the whole. This Romanza without tempo marking (but clearly Andante) is a rondo in ABACA form that plunges dramatically into G minor before the end couplet -- a significant harmonic departure not just here but in the concerto's overall context.

Mozart returns to D minor ion the third movement (Allegro assai; alla breve). Until the coda, we hear one of Mozart's rare rondos in a minor key. More precisely, it is an extended sonata-rondo (ABACDA, plus coda), since C is a development, with the reprise in section D. The development again as before in the second movement seeks out G minor -- the darkest key in Mozart's harmonic lexicon -- before D major is finally allowed to break through, albeit a whitish and wintry sun.