It is evident that such conditions of life would be impossible with town-populations even approaching only distantly those of to-day; and, in fact, when we come to inquire into the size and populousness of mediæval cities, as into those of the classical world of antiquity, we are at first sight staggered by the smallness of their proportions. The largest and most populous free imperial cities in the fifteenth and sixteenth centuries, Nürnberg and Strassburg, numbered little more than 20,000 resident inhabitants within the walls, a population rather less than that of (say) Gloucester at the present time. Such an important place as Frankfurt-am-Main is stated at the middle of the fifteenth century to have had less than 9000 inhabitants. At the end of the fifteenth century Dresden could only boast of about 5000. Rothenburg on the Tauber is to-day a dead city to all intents and purposes, affording us a magnificent example of what a mediæval town was like, as the bulk of its architecture, including the circuit of its walls, which remain intact, dates approximately from the sixteenth century. At present a single line of railway branching off from the main line with about two trains a day is amply sufficient to convey the few antiquarians and artists who are now its sole visitors, and who have to content themselves with country-inn accommodation. Yet this old free city has actually a larger population at the present day than it had at the time of which we are writing, when it was at the height of its prosperity as an important centre of activity. The figures of its population are now between 8000 and 9000. At the beginning of the sixteenth century they were between 6000 and 7000. A work written and circulated in manuscript during the first decade of the sixteenth century, "A Christian Exhortation" (_Ein Christliche Mahnung_), after referring to the frightful pestilences recently raging as a punishment from God, observes, in the spirit of true Malthusianism, and as a justification of the ways of Providence, that "an there were not so many that died there were too much folk in the land, and it were not good that such should be lest there were not food enough for all". Great population as constituting importance in a city is comparatively a modern notion. In other ages towns became famous on account of their superior civic organisation, their more advantageous situation, or the greater activity, intellectual, political, or commercial, of their citizens.