late 14c., from which + ever. Emphatic extended form whichsoever attested from mid-15c.
Entries linking to whichever
which pron.
Old English hwilc (West Saxon, Anglian), hwælc (Northumbrian) "which," short for hwi-lic "of what form," from Proto-Germanic *hwa-lik- (source also of Old Saxon hwilik, Old Norse hvelikr, Swedish vilken, Old Frisian hwelik, Middle Dutch wilk, Dutch welk, Old High German hwelich, German welch, Gothic hvileiks "which"), from *hwi- "who" (from PIE root *kwo-, stem of relative and interrogative pronouns) + *likan "body, form" (source also of Old English lic "body;" see like (adj.)). In Middle English used as a relative pronoun where Modern English would use who, as still in the Lord's Prayer. Old English also had parallel forms hwelc and hwylc, which disappeared 15c.
ever adv.
Old English æfre "ever, at any time, always;" of uncertain origin, no cognates in any other Germanic language; perhaps a contraction of a in feore, literally "ever in life" (the expression a to fore is common in Old English writings). First element is almost certainly related to Old English a "always, ever," from Proto-Germanic *aiwi-, extended form of PIE root *aiw- "vital force, life; long life, eternity." Liberman suggests second element is comparative adjectival suffix -re.
Sometimes contracted to e'er in dialect and poetry. Ever began to be used in late Old English as a way to generalize or intensify when, what, where, etc. The sense evolution was from "at any time at all, in any way" to "at any particular time; at some time or another; under any circumstances." Ever so "to whatever extent" is recorded by 1680s. Expression did you ever? (implying "see/do/hear of such a thing") attested by 1840.