late 14c., necessite, "constraining power of circumstances; compulsion (physical or moral), the opposite of liberty; a condition requisite for the attainment of any purpose," from Old French necessité "need, necessity; privation, poverty; distress, torment; obligation, duty" (12c.), from Latin necessitatem (nominative necessitas) "compulsion, need for attention, unavoidableness, destiny," from necesse (see necessary). Meaning "condition of being in need, want of the means of living" in English is from late 14c.
Necessity is the Mother of Invention. [Richard Franck, c. 1624-1708, English author and angler, "Northern Memoirs," 1658]
To maken vertu of necessite is in Chaucer. Related: Necessities.