The first four piano concertos by Mozart are now known to be orchestrations of sonatas by various German virtuosi. By using movements from the sonatas of other composers, the young Mozart seems to have begun to learn how to cope with the structural problems of composing in the piano concerto form. The concerto is scored for strings, piano (or harpsichord) and pairs of oboes and horns. The first movement is based on the initial allegro of the Sonata op. 1 no. 5 by Hermann Friedrich Raupach, from a set of six published in Paris in 1756. The provenance of the second movement is unknown, although Eric Blom, the editor of the 5th edition of Grove's Dictionary (1954), suggested that it was in fact by Mozart. The final movement is based on the first movement of the Sonata op. 2 no. 3, by the Strasbourg based Leontzi Honauer.
