Collecting materials for a British epidemiology from these various sources is not an easy task; had it been so, it would hardly have been left to be done, or, so far as one knows, even attempted, for the first time at so late a period. Where the sources of information are so dispersed and casual it is inevitable that some things should have been overlooked: be the omissions few or many, they would certainly have been more but for suggestions and assistance kindly given from time to time by various friends. The materials being collected, it remained to consider how best to use them. The existing national epidemiologies, such as that of Italy by Professor Corradi or the older ‘Epidemiologia Española’ of Villalba, are in the form of Annals. But it seemed practicable, without sacrificing a single item of the chronology, to construct from the greater events of sickness in the national annals a systematic history that should touch and connect with the general history at many points and make a volume supplementary to the same. Such has been the attempt; and in estimating the measure of its success it may be kept in mind that it is the first of the kind, British or foreign, in its own department. The author can hardly hope to have altogether escaped errors in touching upon the general history of the country over so long a period; but he has endeavoured to go as little as possible outside his proper province and to avoid making gratuitous reflections upon historical characters and events. The greater epidemic diseases have, however, been discussed freely--from the scientific side or from the point of view of their theory. It remains to acknowledge the liberality of the Syndics of the Cambridge University Press in the matter of publication, and the friendly interest taken in the work by their Chairman, the Master of Peterhouse. _November, 1891._ CONTENTS. PAGE CHAPTER I. PESTILENCES PREVIOUS TO THE BLACK DEATH, CHIEFLY FROM FAMINES. The plague of 664-684 described by Beda, and its probable relation to the plague of Justinian’s reign, 542- 4 Other medieval epidemics not from famine 9 Chronology of Famine Sicknesses, with full accounts of those of 1194-7, 1257-9, and 1315-16 15 Few traces of epidemics of Ergotism; reason of England’s immunity from _ignis sacer_ 52 Generalities on medieval famines in England 65 CHAPTER II. LEPROSY IN MEDIEVAL BRITAIN. Medieval meanings of _lepra_ 69 Biblical associations of Leprosy 79 Medieval religious sentiment towards lepers 81