Up until the 1730s, however, the only Latin texts which Bach had set were a couple of Sanctus movements, and the Magnificat for vespers. The composition of the Missa section of the mass in 1733 was prompted by two events. The first of these was the death of the Elector of Saxony, Augustus the Strong in early 1733. This prompted a five-month period of mourning which included a ban on the public performance of music. This freed up some time for Bach and he appears to have spent this time composing a setting of the Kyrie and Gloria. (Whilst use of the vernacular was a key factor in protestant reforms, some Latin texts did survive in the Lutheran church because they were popular and accessible; the Sanctus, Gloria and Greek Kyrie eleison are examples.) Bach’s intention was to present these movements to the successor of the deceased Augustus the Strong with the hope of being offered a senior musical appointment in Dresden. The second event was the sudden and unexpected vacancy of the post of organist of the Sophienkirche in Dresden at the same time. Bach had given a couple of well received recitals there in the late 1720s, and was keen for his son, Wilhelm Friedemann Bach, to be appointed to the post.

Pulling strings with colleagues in Dresden, and preparing his son rigorously for the appointment process, he was able to accomplish this, and, in the autumn of 1733, accompanied his son to Dresden to help him to settle in to his new position. Whilst in Dresden, Bach presented a beautifully written score and a complete set of parts of a Kyrie and Gloria, those which now constitute the Missa of the Mass in B Minor, to the royal authorities. Bach appears necessarily to have kept the composition of this work secret from his employers in Leipzig; the parts are written in his own hand, and in those of close family members, and show no evidence of having been produced in the sweatshop of the Thomasschule, where his pupils regularly and feverishly transcribed parts from his newly completed cantata manuscripts for imminent performance in Leipzig. Furthermore, some of the parts are written on paper bearing a Leipzig watermark, whilst some are on paper that has clearly been shown to have been purchased in Dresden, indicating that the completion of the copying of the work was carried out whilst he was settling Wilhelm into his new job. There is evidence also that he employed a Dresden copyist, previously unknown to him, in order to get the work completed on time. (Sir John Eliot Gardiner presents extensive research in his book on the way in which these exact parts were produced, and identifies the styles of copying and procedures used by various family members to achieve this; this research is fascinating, meticulous and detailed, but too lengthy to reproduce here.)

It is not surprising that Bach wanted to complete this work behind his employers’ backs, as there would have been no justifiable reason for the composition of such a work for use in the churches in Leipzig, and therefore no obvious occasion for a performance. The Kyrie is divided into four sections: an opening and arousing “call to worship” in the Protestant Lutheran style; a lengthy and complex fugue; a movement for soprano duet and violin obbligato, and a further final fugue in a completely different style. The Gloria begins and ends with big choral movements, which are like bookends to inner movements. It can be no coincidence that these equitably feature each of the soloists in turn (SATB), and contain instrumental solos (or obbligati) from each area of the orchestra, also in turn: violin; flute; oboe d’amore and horn (corno de caccia). The nature of the music of these movements, which employs both the old (stile antico) style, and the new Galant style which was fashionable in Dresden, is different from other work of this period, and the choice of the first two movements of the Latin Mass sits much more comfortably with the Catholic ideology which was present in Dresden than the devoutly Lutheran Leipzig. (Galant is an eighteenth century term used to describe music which, at the time, was thought to be modern and “elegant” or “chic”, as opposed to the more ordered musical language of the Baroque.)

It is, in effect, the first leanings towards the musical language which we now commonly label “classical” and which we associate with the music of Mozart and Haydn and even C.P.E. Bach. The score of this music bears close comparison with the earlier Venetian mass settings which were fashionable in Dresden at this time; settings by composers such as Lotti and Caldara. In Bach’s mind, we can assume the most desirable outcome of this exercise to have been a performance of the work at the Sophienkirche, in front of the new Elector, directed either by himself or by the newly appointed Wilhelm Friedemann. This would not have been out of place, as the Dresden court musicians often performed Italian mass settings of a more elaborate and operatic style at the celebration of High Mass at the Sophienkirche on major feast days, supported by a troupe of trained opera singers recruited by the Dresden Court from Italy in the early 1730s. These were adult singers (including castrati) with experience, stamina and technique; not merely boys from a school such as those for whom Bach was accustomed to writing.