Mid 17th century; earliest use found in George Tooke (1595–1675), army officer and writer. From French allons, 1st person plural imperative of aller to go from post-classical Latin alare, ultimately a variant (with loss of the unstressed medial -u- and subsequent assimilation of consonants, although the exact phonological history is unclear) of classical Latin ambulāre to walk. See further Französisches etymol. Wörterbuch XXIV. at ambulare.