The postal history of Malta began in the early modern period, when pre-adhesive mail was delivered to foreign destinations by privately owned ships for a fee. The earliest known letter from Malta, sent during the rule of the Order of St John, is dated 1532. The first formal postal service on the islands was established by the Order in 1708, with the post office being located at the Casa del Commun Tesoro in Valletta. The first postal markings on mail appeared later on in the 18th century.