Mozart composed The Coronation Mass (Krönungsmesse KV 317) in 1779. It's one of the most popular of his 17 extant settings of the 'Ordinary of the Mass'. This setting, like the majority of Mozart's mass settings, is a 'Missa brevis', or short mass (as opposed to the more formal 'Solemn Masses' or 'High Masses', known as Missae solemnes). The mass appears to have acquired the nickname Coronation at the Imperial court in Vienna in the early nineteenth century, after becoming the preferred music for royal and imperial coronations as well as services of Thanksgiving. Whether it was performed at the coronations of Leopold II in 1790 and Francis II in 1792, as some sources assume, is unlikely.