'whoever' originates from Old English elements: the interrogative pronoun 'hwa' (who) combined with the Old English adverb 'ǣfre' (ever).

'whoever' changed in Middle English to forms such as 'who-euer' or 'whoever', and eventually became the modern English word 'whoever'.

Initially the components expressed 'who' + 'ever' (an emphatic or generalizing 'ever'); over time the fused form came to mean 'any person who' or 'no matter who'.