Excellent articles, indeed, such as those from the pen of [p-xv] Professor Seebohm and Dr. Jessop, and chance pages in books on political and social economy, like those of the late Professor Thorold Rogers and Dr. Cunningham, have done much in our time to draw attention to the importance of the subject. Still, so far as I am aware, no writer has yet treated the plague as a whole, or, indeed, has utilised the material available for forming a fairly accurate estimate of its ravages. The collections for the present study had been entirely made when a book on the _Epidemics in Britain_, by Dr. Creighton, was announced, and, as a consequence, the work was set aside. On the appearance of Dr. Creighton's volume, however, it was found that, whilst treating this pestilence at considerable length as a portion of his general subject, not merely had it not entered into his design to utilise the great bulk of material to be found in the various records of the period, but the author had dealt with the matter from a wholly different point of view. It is proper, therefore, to state why a detailed treatment of a subject, in itself so uninviting, is here undertaken. The pestilence of 1348-49, for its own sake, must necessarily be treated by the professional writer as an item in the general series of epidemics; but there are many reasons why it has never been dealt with in detail from the mere point of view of the historian. Yet an adequate realisation of its effects is of the first importance for the right understanding of the history of England in the later [p-xvi] Middle Ages. The "Black Death" inflicted what can only be called a wound deep in the social body, and produced nothing less than a revolution of feeling and practice, especially of religious feeling and practice. Unless this is understood, from the very circumstances of the case, we shall go astray in our interpretation of the later history of England. In truth, this great pestilence was a turning point in the national life. It formed the real close of the Mediæval period and the beginning of our Modern age. It produced a break with the past, and was the dawn of a new era. The sudden sweeping away of the population and the consequent scarcity of labourers, raised, it is well recognised, new and extravagant expectations in the minds of the lower classes; or, to use a modern expression, labour began then to understand its value and assert its power.