Mozart visited Italy with his father in 1770, writing several symphonies and an opera, Mitridate, rè di Ponto, while there. The pair returned to Salzburg in March 1771, and in July Mozart produced this G major Symphony, which broke somewhat from the Italian influence noticeable in the three-movement symphonies immediately preceding it. The Symphony No. 12 consists of four movements, with two outer Allegros framing an Andante and Menuetto.
The first movement opens with a vibrant, joyous theme of mostly rising contour played by the strings. The second subject glides downward playfully and bounces smartly back up. A second theme, given by oboes, offers imaginative contrast in its initially subdued character, but it, too, springs to life vibrantly. Thematic development is relatively limited here and does not break from the bright, energetic mood of the expository sections.
The ensuing Andante features a charming, spirited theme (livelier than its tempo marking might normally suggest), first played by the strings. Flutes and bassoons are added to the scoring here along with some humorous touches: listen to the deliberately sour downward swoops by the strings. This cheerful slow movement is followed by an elegant Minuet that features a subdued trio for strings that deftly mixes the mysterious with the playful. The Finale, at just over two minutes, is the shortest movement here, but easily the most effervescent and energetic. The ebullient main theme seems to wind up, then tumble gracefully downward, only to go through the process again and again. The brief middle section alternates somewhat tranquil, almost dreamy music with boisterous, hearty music. While this symphony is not one of Mozart's most popular or inspired efforts, it is nonetheless a strong work of undeniable charm.