late 14c., "to ask a question, inquire," from Old French requerre "seek, procure; beg, ask, petition; demand," from Vulgar Latin *requaerere, from Latin requirere "seek to know, ask," from re-, here perhaps meaning "repeatedly" (see re-), + quaerere "ask, seek" (see query (v.)).
The original sense of this word has been taken over by request (v.). Sense of "demand (someone) to do (something)" is from 1751, via the notion of "to ask for imperatively, or as a right" (late 14c.). Related: Required; requiring.