Yours, Etc.: Origins and Uses of 8 Sign-Offs
1917, "outward or social personality," a Jungian psychology term, from Latin persona "person" (see person). Used earlier (1909) by Ezra Pound in the sense "literary character representing voice of the author." Persona grata is Late Latin, literally "an acceptable person," originally applied to diplomatic representatives acceptable to the governments to which they were sent; hence also persona non grata (plural personæ non gratæ).
persona per·so·na (pər-sō'nə)
n. pl. per·so·nas or per·so·nae (-nē)
The role that one assumes or displays in public or society; one's public image or personality, as distinguished from the inner self.
A person who is no longer favored or welcome: “After my angry words with the manager, I am persona non grata at the video store.” From Latin, meaning “an unacceptable person.”
in literature, the person who is understood to be speaking (or thinking or writing) a particular work. The persona is almost invariably distinct from the author; it is the voice chosen by the author for a particular artistic purpose. The persona may be a character in the work or merely an unnamed narrator; but, insofar as the manner and style of expression in the work exhibit taste, prejudice, emotion, or other characteristics of a human personality, the work may be said to be in the voice of a persona