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The Missa in B minor, BWV 232a, by Johann Sebastian Bach is a setting of two parts of the Latin mass, Kyrie and Gloria. Bach composed the two sections, each in several movements, in Leipzig in 1733 for the court in Dresden. It is also known as Missa 1733. Bach later derived cantata Gloria in excelsis Deo, BWV 191, from three movements of the Gloria (1745) and included both Kyrie and Gloria unchanged into his Mass in B minor, BWV 232.
History
Bach was a Lutheran church musician, devoted to the composition of sacred music in German. He wrote more than 200 cantatas for the liturgy, most of them in Leipzig. In 1724 he composed a Sanctus for Christmas, which he later integrated into his Mass in B minor. In 1733 he composed a Missa, a setting of Kyrie and Gloria, for the court of Dresden, the Kyrie as a lament for the death of Augustus the Strong, King of Poland and Elector of Saxony, who had died on 1 February 1733 (he had been received into the Catholic Church in order to ascend the throne of Poland in 1697.) The Gloria was to celebrate his successor, later Augustus III of Poland. Bach presented parts of the works to Augustus with a note dated 27 July 1733, in the hope of obtaining the title, "Electoral Saxon Court Composer", complaining that he had "innocently suffered one injury or another" in Leipzig. The works were performed in 1733, most likely at the Sophienkirche in Dresden, where Bach's son Wilhelm Friedemann Bach had been organist since June, though not in the presence of their dedicatees.
Later, Bach used three movements of this Gloria to compose his cantata Gloria in excelsis Deo, BWV 191, possibly for a performance in 1745. Bach integrated the complete Missa unchanged in his Mass in B minor, his only complete mass (or missa tota). Scoring and structure are identical with the later work.
Bach described the piece as "an insignificant product of the skill I have attained in music." Hans Georg Nägeli described the work, in 1818, as "the greatest musical art work of all times and nations."
An English translation of the letter is given in Hans T. David and Arthur Mendel, The Bach Reader: A Life of Johann Sebastian Bach in Letters and Documents, W. W. Norton & Company, 1945, p. 128. (Also in "The New Bach Reader: A Life of Johann Sebastian Bach in Letters and Documents" revised by Christoph Wolff, W. W. Norton & Co Inc, 1998, ISBN 978-0-393-04558-1 , p. 158.)
Sophienkirche, Dresden, possibly the location of the first performance
