Presented here is a manuscript transcription of the Symphony Number 48, commonly known as the Maria Theresia Symphony, by Joseph Haydn (1732−1809). The original of the composition was not preserved in Haydn’s own hand, but this manuscript was created by the composer’s most important copyist, Joseph Elssler (died 1782). It dates from 1769 and is the oldest known manuscript of this composition. The date of the document proves that Haydn did not compose this work on the occasion of the visit of Empress Maria Theresia to the summer residence of the Esterházy family in 1773, as had been previously assumed. The complete title of the symphony is given, in Italian, as Synfonia in C. Violino Primo. Violino Secondo. Oboe Primo. Oboe Secondo. Corno Primo. Corno Secondo. Viola col Violone. Del Signore Giuseppe Haydn, Inter Difficillimo Numero II (Symphony in C, number 48. First violin. Second violin. First oboe. Second oboe. First horn. Second horn. Viola with violone. By Sir Joseph Haydn. Very difficult interpretation. Number 2.)