The concerto was written in Vienna some time among the top of September and the beginning of October 1791. The achieved score was sent off to Stadler in Bohemia and it bought its first functionality at Stadler’s advantage live functionality in the Prague Theatre on October 16, 1791. Seven weeks later, Mozart was dead. Even in Mozart's day, the basset clarinet was a rare, custom made device, so when the piece was published posthumously, a new edition was ready with the low notes transposed to average range. This has proven a not easy choice, as the autograph not exists, having
been pawned by Stadler, and until the mid 20th century musicologists did not know that the one model of the concerto written by Mozart's hand had not been heard since Stadler's lifetime. Once the problem was found, attempts were made to reconstruct the normal edition, and new basset clarinets were built for the true goal of performing Mozart's concerto and clarinet quintet. There can not be any doubt that the concerto was composed for a clarinet with an extended range. In this context it is worth noting two other works written for Stadler and his tool by composers carefully linked to the Mozart–Stadler circle that used the lengthy range of Stadler's tool: the clarinet concerto by Franz Xaver
Süssmayr famous for having carried out Mozart's Requiem and that by Joseph Leopold Eybler. The beginning orchestral ritornello is joyful and light-weight-weight, and shortly transforms into a flurry of sixteenth notes in descending series, played by the violins and flutes while the lower gadgets drive the piece ahead. After the medial caesura, the strings begin a sequence of canons before the first closing theme, that includes dueling violin I's and violin II's, enters. The second last theme is a lot more subtle until the fanfare of its final 2 bars.