Durchlauchtster Leopold in D major, BWV 173a

Bach composed the cantata as a congratulatory cantata, also termed serenata, for the 28th birthday of his employer, Leopold von Anhalt-Köthen, on 10 December 1722. The relatively simple work may have been written in some haste already in 1717, when Bach had been appointed Kapellmeister, according to Alfred Dürr. However, this is not likely[original research?], because Bach was still in the process of moving to Köthen on 10 December 1717 (having been released from his imprisonment in Weimar on 2 December 1717). The libretto even shows a date of "before 22 December 1722". So, in all probability, the work and first performance of it date from 10 December 1722.