Missa in C major K. 259 "Organ Solo Mass"

When Anton Theodor of Colloredo was ordained as Archbishop of Olmütz in 1778, the prince archbishop left the selection of music to Kapellmeister Leopold Mozart. The work he chose was Wolfgang Amadeus Mozart’s “Missa in C major” K. 259, composed in 1775/76. On account of the soloistic organ part in the “Benedictus”, the work is also known as the “Organ Solo Mass”. As the Kapellmeister deemed the “Kyrie” too short and not solemn enough for the occasion, he replaced it with the “Kyrie” from the “Spaur Mass” K. 258. He also possibly altered the orchestration of the work, adding two oboes. The copyist of the parts did not use the autograph, but rather a copy, in which an unknown person – perhaps Mozart himself – had already made cuts to the “Benedictus”. Copies of the original as well as the shortened “Benedictus” have been preserved, meaning that both versions of the work were copied – first the original, and later the version containing the altered “Benedictus”. In his edition, editor Walter Senn accounts for the different versions of the work with regard to its sources and genesis: The cuts in the “Benedictus” are marked with “vi – de”, and the oboe parts have been added to the main text.