1630, in the meaning defined at sense 1a

borrowed from French cajoler "to give much attention to, make a fuss over, flatter, persuade with flattery," going back to Middle French cajoller "to flatter out of self-interest," perhaps the same verb as Middle French cageoller "to vocalize, sing (of a jay or other bird)," expressive formation of uncertain origin

NOTE: Middle French cageoller was explained by Wartburg, et al., Französisches etymologisches Wörterbuch, as a permutation, under the influence of cage cage entry 1, of gaioler "to chatter, cackle (of birds)," a derivative of Picard gaiole "birdcage," corresponding to Old French geole, jaole "cage, prison" (see jail entry 1). According to Dubois-Mitterand-Dauzat, Dictionaire étymologique et historique du français (Larousse, 1993, continuing the etymology from earlier editons of Dauzat), the meaning "to flatter" is due to association of cageoller with enjôler "to captivate by flattery" (Old French enjaoiler "to imprison"). Alternatively, the two formations ("to sing, vocalize" and "to flatter") have been regarded as of independent origin; the first may either be an onomatopoeic outgrowth of cacarder "to honk (of a goose)," or a rearrangement of *jacoler, based on jacques, a dialectal name for a jay; the second is conjecturally a merger of enjôler and caresser "to stroke, caress entry 1" (thus E. Gamillscheg, Etymologisches Wörterbuch der französischen Sprache, 2. Auflage, Winter, 1969).