
1) Opera by Henry Purcell
Found on
https://www.crosswordclues.com/clue/dioclesian

Dioclesian (The Prophetess: or, The History of Dioclesian) is a tragicomic semi-opera in five acts by Henry Purcell to a libretto by Thomas Betterton based on the play The Prophetess, by John Fletcher and Philip Massinger, which in turn was based very loosely on the life of the Emperor Diocletian. It was premiered in late May 1690 at the Queen`s ....
Found on
http://en.wikipedia.org/wiki/Dioclesian

(from the article `Purcell, Henry`) ...was constantly employed in writing music for the public theatres. These productions included some that gave scope for more than merely incidental ...
Found on
http://www.britannica.com/eb/a-z/d/51
No exact match found.