Schuberts ninth symphony was written near the end of his life and completely finished in 1826. Schubert didn’t have any money, so he couldn’t afford a performance. It was not commissioned, so he sent it to the Musikverein in Vienna. That is the club that in 1970 built the famous golden hall most Europeans can see each year at the New Year’s Eve concert. It got enough attention there for them to actually make copies and do some trials. Then it was laid aside: it was deemed too long and complicated for the orchestra that was still in its infancy. It was not performed before Robert Schumann discovered lying around in Vienna and took it with him to Leipzig. There it was performed by the Gewandhausorchester. It was ten years after Schubert’s death.
The ninth symphony of Schubert that might actually be his seventh, or so it is in Germany. It is numbered 8 in the latest edition of the Deutsch catalogue. Schuberts works are catalogued with a “D” number, that stands for Otto Erich Deutsch, who published his extensive catalogue in 1951.