Late 20th century to present.
An exclamation frequently made by the Boy Wonder-aka Robin-from Batman and Robin, the TV series. It has found its home in contemporary American slang vernacular as a way to exclaim surprise at something, while conveying a mixed sense of genuine dumbfoundedness and nonchalance.
Replace "X" with a noun, verb,an adjective-noun/verb pair, and anything else that fits.
"Holy gay fetish xxx porn, Batman!"
"Holy sophisticated ejaculation, Batman!"