I. Allegro con brio; II. Largo; III. Rondo. Allegro scherzando

Beethoven arrived in Vienna in November 1792 where he bowled over salon audiences with his piano playing, particularly his improvising. It is no surprise that the young titan soon turned to the genre in which he could best demonstrate his capabilities as both composer and instrumentalist: the piano concerto. Around 1794-1795, Beethoven worked on two concertos simultaneously, one in B flat major, the other C major. Although he completed the B flat concerto in early 1795 and had it performed at the Burgtheater in spring that year, he later revised the work, only completing it to his satisfaction in 1798 after he had finished the C major concerto. This is why the C major concerto was published as opus 15 while the B flat concerto received the opus number 19. Neither can be regarded as Beethoven's first piano concerto: this honour belongs to a work in E flat major which he composed in 1784, although only the piano part from this has survived.

In his monograph on Beethoven, the distinguished Hungarian musicologist Bence Szabolcsi notes that the two piano concerto written between 1794 and 1798 are less mature and individual than the piano sonatas composed over the same period (opp. 2, 7. 10). Mozart's influence is most readily apparent in the Piano Concerto in C major although many details explicitly predict Beethoven's later symphonic expansiveness. We can also observe many individual features in the piano writing. This is partly because Beethoven – as did Mozart – shaped the work around his own individual capabilities as a pianist: for example he was clearly fond of striking powerful gestures. But the concerto was written at a time when the keyboard instruments were undergoing a tremendous development: the range of notes increased, as did their power which naturally broadened the expressive range of these pianos. The treatment of tonality in the C Major Piano Concerto is also recognisably Beethovenian. For example, the slow movement is in relatively remote key of A flat major. “This unusual tonality shows that Beethoven was preoccupied at this time with triadic relationships; the tonality of C minor would appear the most fitting for the “profound” mood and one cannot help feeling that for Beethoven, there is some unexpressed minor tonality lurking beneath this major key” wrote Szabolcsi. In truth, besides the choice of tonality for the central section, there is also the evidence of the opening movement exposition in which the secondary theme is cast in E flat major. But the first episode of the closing sonata rondo, which after the “compulsory” dominant tonality, G major, also turns to E flat major.
The principal theme of the opening movement, even on its first hearing in pianissimo, virtually brands itself onto the listener's memory – its principal element is rhythm. But the other two thematic ideas of the movement also possess striking features: the secondary theme is constructed on an alternation between a subtle, flexible melody and a response from the woodwind, while the closing theme evokes march music. The miraculously soft sonority of the Largo owes much to the role given to the clarinets which permeate and supplement the soloist's melodies. The German folksong themes of the closing movement are employed with Beethoven's typically robust humour and inventiveness. He premiered the Piano Concerto in C major in 1798 and it was printed in 1801.