Mozart composed his C-minor Piano Concerto as he was writing The Marriage of Figaro, and he gave it its world premi?re at the Burgtheater in Vienna in April 1786. It involves the largest orchestral apparatus Mozart ever used, with trumpets, horns, kettledrums, and the entire range of woodwind (flute, two oboes, two clarinets and two bassoons) which have important solo roles. The chromaticism and passionate character typical for the C minor key is associated with the main theme of the opening movement, one that will keep returning later on. The piano has its own main theme which is, conversely is contemplative and melancholic. Its cheerful E-flat-major second theme is followed by a lyrical third theme played by the wood section. Masterfully combined in a balanced unit, this multitude of musical characters is evocative of the totality of opera.

 
Speaking in Mozart’s characteristic romance vernacular, the rondo theme of the E-flat-major slow movement begins with the piano; however, the completely equal woodwinds (oboes and two clarinets) play two of its episodes. In the relatively slow third movement the theme is played by the full orchestra, and is followed by eight variations. Mozart ensures diversity in the variations through orchestration and variety of character. The fourth and the sixth switch to C major, and the fifth is composed in a Baroque manner, strictly in four parts. In the last variation following the piano cadenza, the music changes from double to triple time (3/8); however, the shift to the minor key that often follows minor-key finales is omitted in this case, and the movement ends with some confident chords in C minor.