prologist

noun

1. (rare)The writer or speaker of a prologue.

   “The following Play…The Prologist and Epilogist represent the whole Course of Literature.”

   “Such a prologist as Sir Dudley seemed scarcely to threaten.”

   “The principal characters in the play appear to have been grouped in a kind of tableau on the stage while the prologue was delivered, in this as in some other plays. The prologist informs the audience that the two captives who stand in chains on his right and left, are Philocrates, a young noble of Elis, and his slave Tyndarus.”