One of the forms that began a long history of development was that of the symphony,which is a work of more than one movement, with at least one of the movements in sonata form. Sonata form can be viewed as the defining compositional form of the Classical era. There were many composers who used sonata form and added to the development of it, with one of the earliest being Giovanni Battista Sammartini.
Sammartini was a prolific Italian composer who composed works in many different genres, but
is most well known for his 68 extant symphonies which were written throughout his long life (1700-1775). He remained in the Milan area all of his life, but his music became well known to other composers and he met many of his contemporaries, including Mozart. Two symphonies Sammartini composed in 1732 are what musicologists believe constitute earliest dated symphonies known. And coincidentally, 1732 is the birth year of one of the most famous symphony composers in classical music, Joseph Haydn.
His works were forgotten shortly after his death and it wasn't until 1913 that he was rediscovered. The J-C numbers listed after Sammartini's works are from the musicologists Newell Jenkins and Bathia Churgin catalogue of Sammartini's known works in 1976. Symphony In C Minor J-C 9 is believed to be an early work written between 1730-1750 scored for strings and continuo, and is in three movements:
I. Allegro - The first movement begins with a dotted rhythm theme in C minor that lasts for ten measures. The theme modulates to E-flat major and is expanded to fourteen measures long. The number of measures in the theme gives it a feeling of being slightly off balance phrase wise in both versions. The second section has the theme modulate to other keys and settles on G, the dominant of the home key. The theme returns in the original key of C minor and after a few short modulations the theme ends in C minor. The movement is an early version of sonata form that used a variant of the msin theme as a contrasting second theme, a method used later by Haydn in some of his sonata form movements.
II. Affettuoso - The second movement is written in E-flat major in simple binary form. The first section is 18 measures. the second section is extended to 22 measures, which like the first movement makes for unequal phrasing.
III. Allegro - As in the first movement, Sammartini uses one theme and varies it to achieve the semblance of a different theme. Triplets and sharp staccatos add to the velocity of the music, and it ends in C minor.