c.1225, from O.Fr.
menestral "entertainer, servant," from M.L.
ministralis "servant, jester, singer," from L.L.
ministerialem (nom.
ministerialis) "imperial household officer, one having an official duty," from
ministerialis (adj.) "ministerial," from L.
ministerium (see
ministry). The connecting notion is via the jester, etc., as a court position. Specific sense of "musician" developed in O.Fr., but in Eng. until 16c. the word was used of anyone (singers, storytellers, jugglers, buffoons) whose profession was to entertain patrons. Only in 18c. was the word limited, in a historical sense, to "medieval singer of heroic or lyric poetry who accompanied himself on a stringed instrument." Ref. to blackface music acts in U.S. is from 1843.
Minstrelsy is 13c. Anglo-Fr.
menestralsie, from O.Fr.
menestrel.