Bach completed the Mass in B Minor and, so far as the documentary record shows, never once heard it performed in full. Individual movements had circulated, the 1733 Kyrie and Gloria were performed at least in Dresden, but the finished whole he assembled in his last two years was too long, too demanding and addressed to no specific occasion, so no institution had reason to mount it complete while he was alive to hear it. He died in July 1750, roughly a year after finishing it.
More than a century passed before anyone did. The work's first documented complete performance took place in Leipzig, the city where Bach had spent his final decades, in 1859, conducted by Karl Riedel with the choir he had founded, the Riedel-Verein. By then Bach's reputation had already been substantially restored by the earlier revival of his St Matthew Passion, itself first heard again only in 1829 under a twenty-year-old Felix Mendelssohn; the Mass followed the same pattern of near-total neglect followed by rediscovery, on an even longer delay.
Today the gap between composition and premiere reads as one of the stranger facts in the whole Western canon: a work now ranked among its summit achievements, over 350 complete recordings on record as of 2022, was authored across sixteen years, finished, and then sat unperformed as a whole for more than a hundred more. Bach's own St Matthew Passion, seeded in this atlas's second band of media works, at least had one Good Friday liturgy in 1727 to call its own. The Mass in B Minor never had even that.