K. 45 Symphony No 7 in D Major,

Symphony No. 7 in D major, K. 45, by Wolfgang Amadeus Mozart, was completed in Vienna in January 1768 after the family's return from a visit to Olomouc and Brno in Moravia. The symphony is in four movements. Its first performance was probably at a private concert. The symphony was reworked to become the overture to Mozart's opera, La finta semplice, K. 51, composed and performed later that year, and the overture itself was subsequently adapted further to create a new symphony, known in the Köchel 1964 (K6) catalogue as K. 46a. The autograph of the score is preserved in the Staatsbibliothek Preusischer Kulturbesitz in Berlin.

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