[90] Non-european indigo is already mentioned in Medieval financial records in the twelfth and thirteenth centuries and in Venetian dyers’ regulations in the fourteenth century, but imported indigo long remained prohibited in Europe for dyeing wools, as is evidenced in one of the oldest statutes concerning the art of wool dyeing from Florence (1317).  See Dominique Cardon, Le monde des teintures naturelles (Paris: Belin, 2014), 357-358.