"[Martinists] studie to pull downe Bishopps, and set vp Superintendents, which is nothing else, but to raze out good Greeke, & enterline bad Latine." [Lyly, "Pappe with an Hatchet," 1589]The general sense of "a person who has charge of some business" is first recorded 1588. Meaning "janitor, custodian" is from c.1935. Shortened form super first attested 1857, especially at first of overseers of sheep ranches in Australia.
"So was created ... Superman! champion of the oppressed, the physical marvel who had sworn to devote his existence to helping those in need!" ["Action Comics," June 1, 1938]
Superwoman first recorded 1976 in the sense of "one who combines career and motherhood."