Origin and history of wherefrom

Old English fram, preposition denoting departure or movement away in time or space, from Proto-Germanic *fra "forward, away from" (source also of Old Saxon, Old High German, Gothic fram "from, away," Old Norse fra "from," fram "forward"), from PIE *pro-mo-, suffixed form of *pro (see pro-), extended form of root *per- (1) "forward." The Germanic sense of "moving away" apparently evolved from the notion of "forward motion." It is related to Old English fram "forward; bold; strong," and fremian "promote, accomplish" (see frame (v.)).

"at or in any place, anywhere," Middle English wher, from Old English hwær, hwar "at or in what place," from Proto-Germanic adverb *hwar (source also of Old Saxon hwar, Old Norse hvar, Old Frisian hwer, Middle Dutch waer, Old High German hwar, German wo, Gothic hvar "where"), equivalent to Latin cur, from PIE root *kwo-, stem of relative and interrogative pronouns.

Where it's at attested from 1903 as "true or essential nature;" by 1971 as "place of central activity."

It has figured in a great many prepositional and adverbial compounds through the years; in addition to the entries given (whereas, wherefore, whereabouts, etc.) English has or had whereagainst, wherehence, whereinsoever, whereinto, wheremid, whereout, whereover, wheresoever, whereunder, and whereuntil, wherewhile.