Preindustrial Period. Postal systems—networks of transportation dedicated to the dissemination of letters and written messages—have a long history. The ancient Greek, Roman, Persian, and Chinese empires each developed complex systems of runners and routes for the conveyance of messages. These complex systems atrophied in Europe and the Mediterranean during the medieval period, where the most important communication networks were run not by the state but rather by universities (such as the University of Paris), monastic orders (such as the Benedictines), and commercial communities (such as the Hanseatic League). In the early modern period, royal courts again assumed responsibility for the key networks of messengers, frequently opening them up to public use while at the same time keeping them under strict surveillance. In the late eighteenth century, postal networks within Europe expanded as increasingly complex road systems reached further...