Plagues and Peoples (21 page)

In China as in the Mediterranean, outbreaks of bubonic plague must have depended on the prior dispersal of the black rat and its fleas. Rats may have taken a few centuries to work their way into the local life balances in sufficient numbers to
create the conditions for really large-scale outbreaks of human plague. At any rate, a series of epidemics broke out in the coastal provinces of China, beginning in the year 762, when “more than half the population of Shantung province died,” and recurred from time to time until 806, when the same high rate of mortality was reported for Chekiang province.
⁸²

On the basis of this imperfect evidence, then, the disease history of China in the early Christian centuries seems to have resembled that of the Mediterranean lands, inasmuch as new and lethal infections probably arrived in China, traveling both overland and across the sea. Moreover, there is sufficient reason to believe that Chinese population dropped sharply from the total of about 58.5 million recorded in
A.D
. 2. As in the Mediterranean lands, decay of population brought with it disruption of administration, and the records that survive are both fragmentary and unreliable. When another more or less dependable census becomes available for China, in
A.D
. 742, the number of hearths recorded was about 8.9 million, whereas in
A.D
. 2 a total of 12.3 million hearths had been registered. In between, various fragmentary statistical returns suggest far more drastic depopulation of certain parts of China, especially in the South where comparative security from raiding nomads was perhaps more than counterbalanced by the heavier disease risk to which peasants pursuing a Chinese style of cultivation were liable. By the middle of the fifth century, for instance, the region around Nanking on the middle Yangtze registered only one fifth as many hearths as in the year 140. Decay in the North, while substantial, was proportionately not so great.
⁸³

There are other and well-known parallels between Roman and Chinese history in these centuries. The fabric of imperial administration broke down in China with the end of the Han Dynasty in
A.D
. 220. Invasions from the steppes and political fragmentation ensued, and by the fourth century as many as sixteen rival states competed for control of China’s northern provinces. Maximal political fragmentation coincided almost exactly with the putative arrival of smallpox and/or measles in
China in
A.D
. 317, and if mortality was anything near the severity recorded by Ssu-ma Kuang (“one or two out of a hundred survived”) it is easy to see why. The figure of 2.5 million hearths in
A.D
. 370 as against 4.9 million hearths for the same region of northern China in
A.D
. 140 may indeed be more credible than scholars who have not bethought themselves of the disease variable are inclined to believe.
⁸⁴

As of
A.D
. 589 China achieved political unification once again, whereas Justinian’s parallel effort (reigned 518–65) to re-establish a Roman empire of the Mediterranean failed. One difference was that Justinian’s empire was weakened by repeated exposure to plague from 542 onward, whereas comparably severe plague attacks do not seem to have occurred in China until after 762, and then they affected only coastal provinces. Nevertheless, the breakup of effective central authority in China subsequent to a great military revolt of
A.D
. 755 did coincide rather closely with these outbreaks of plague. Disease as crippling to a vulnerable population as bubonic plague normally is may well have made it impossible for the imperial authorities to gather sufficient resources from the coastal provinces (which were unaffected by the revolt) to be able to put down the rebellion. Instead, the emperor called upon the help of nomad Uighur armies. As victors, the Turkish-speaking Uighurs were in a position to dictate terms, and speedily siphoned off a considerable part of the imperial resources for their own uses.

Religious history also offers another striking parallel between Rome and China. The Buddhist faith began to penetrate the Han empire in the first century
A.D
., and soon won converts in high places. Its period of official dominance in court circles extended from the third to the ninth centuries
A.D
. This obviously parallels the successes that came to Christianity in the Roman empire during the same period. Like Christianity, Buddhism explained suffering. In the forms that established themselves in China, Buddhism offered the same sort of comfort to bereaved survivors and victims of violence or of disease as Christian faith did in the Roman world. Buddhism
of course originated in India, where disease incidence was probably always very high as compared with civilizations based in cooler climates; Christianity, too, took shape in the urban environments of Jerusalem, Antioch, and Alexandria where the incidence of infectious disease was certainly very high as compared to conditions in cooler and less crowded places. From their inception, therefore, both faiths had to deal with sudden death by disease as one of the conspicuous facts of human life. Consequently, it is not altogether surprising that both religions taught that death was a release from pain, and a blessed avenue of entry upon a delightful afterlife where loved ones would be reunited, and earthly injustices and pains amply compensated for.

The rhythms of population recovery offer yet another parallel between East and West. By the latter part of the tenth century, Chinese populations, like those of northwestern Europe, seem to have achieved a successful biological accommodation to whatever new infections had assailed their forefathers in the preceding centuries. Human numbers began to grow at a pace to produce a population for the entire country of about 100 million by
A.D
. 1200.
⁸⁵
To achieve such mass, two things were needed: a suitable microparasitic accommodation to the ecological conditions of the Yangtze Valley and regions farther south, and a regulated macroparasitism that left enough of their product with the Chinese peasants so that they could sustain a substantial rate of natural increase over several generations. Only then could the teeming millions of rice paddy farmers fill up the relatively vast spaces of central and southern China.

The biological adjustments required for survival in southern China probably took a long time. Signs of really dense populations in the Yangtze Valley and farther south do not become very noticeable until the eighth century; and only under the Sung Dynasty (960–1279) does anything like the population density familiar from ancient times in the Yellow River valley begin to exist in the Yangtze and other southern areas. As we saw in
Chapter II
, malaria, bilharzia, and dengue
fever were probably among the major obstacles to Chinese penetration southward. Variations of inherited human resistance to these infections, together with very delicate balances between different species of mosquitoes, the prevalence of different kinds of warm-blooded animals (humanity being only one possible supplier of blood for mosquitoes, after all), and the virulence of the infectious organism itself, undoubtedly controlled the incidence and seriousness of these diseases. But we cannot expect to recover details of how Chinese peasants learned to survive and flourish in the South with the densities their style of rice paddy cultivation allowed. It is enough to realize that this adjustment was probably not perfected until after
A.D
. 700, and full occupancy was not attained until about 1100.

As for the macroparasitic side: with the establishment of the Sung Dynasty in
A.D
. 960 a relatively successful bureaucratic system spread throughout most of China (the northern tier of provinces remained under barbarian masters), and a remarkably rational pattern for training and selecting high officials became normal. While no one supposes that official oppression ceased, its scope may have been less under the Sung than in earlier times, since systematic supervision of the official class tended to check at least the more flamboyant form of corruption. The massive expansion of population into the South proves that traditional rents and taxes were set at a level that allowed the peasantry to thrive on hard work in the fields, at least as long as sufficient new land could be brought under cultivation to absorb surplus offspring.

Thus China apparently paralleled Europe’s disease experience fairly closely in the centuries with which we are here concerned, arriving at a balance between micro- and macroparasitism that was, in the short run at least, more successful than that of the West. In Europe, after all, local self-defense by formidable arrays of knights did not guarantee peace, since knights and their feudal superiors frequently fell to fighting among themselves, thereby damaging peasant life and production. China’s bureaucratic imperial administration
was clearly superior from this point of view, as long as it continued to be able to ward off attack from the warlike barbarian peoples of the North and West. From the microparasitic side, too, one can rightfully say that the Chinese achievement was superior in the sense that Chinese populations moved up a disease gradient in learning to live successfully in warmer, wetter lands; whereas the shift of European populations toward the North was a movement down a disease gradient into lands where exposure to infestation was naturally less, thanks to cooler temperatures and longer periods of freezing winter weather.

China’s superior success in accommodating to altered conditions of micro- and macroparasitism was reflected in the country’s religious and cultural history. For after 845, Buddhism was replaced as a religion of state by a revived and elaborated Confucianism. It was as if Charlemagne, in reviving the title of Roman Emperor, had also restored paganism as the court religion. Buddhism, of course, continued to exist in China, appealing mainly to peasants and other uneducated classes. But victorious Confucianism absorbed and made its own some of the metaphysical doctrines that had helped to attract the court to Buddhism in the first place. Thus the antibodies that imported diseases provoked and sustained in Chinese bloodstreams had their analogues in the Buddhist themes engrafted into official Confucianism. For the new doctrines received into official Confucianism constituted moral and intellectual antibodies against the charms which Buddhist (and other alien) paths to salvation continued to exert among the lowly and uneducated classes.

Japan’s geographical position obviously tended to insulate the archipelago from disease contacts with the world beyond. This was, however, a mixed blessing, for insulation allowed relatively dense populations to develop which were then vulnerable to unusually severe epidemic seizure when some new infection did succeed in leaping across the water barrier and penetrating the Japanese islands. Japanese rural populations remained much sparser than was the case in China, at least
until rice paddy farming established itself also in Japan (a process still under way in the seventeenth century); and Japanese cities remained much smaller than those of China until quite recent times. This meant that a number of important and lethal diseases that became chronic in China could not establish themselves lastingly among the Japanese until about the thirteenth century. Consequently, for more than six hundred years, before Japan’s population density surpassed the critical threshold that allowed these epidemics to subside into endemic infections, the islands suffered a long series of severe disease invasions.

The first recorded contacts with the mainland came in
A.D
. 552, when Buddhist missionaries from Korea first set foot on Japanese soil. The newcomers brought with them a new and lethal disease—perhaps smallpox.
⁸⁶
A similar severe outbreak occurred again a generation later, in 585, by which time immunities arising from the epidemic of 552 would have worn themselves out. A far more sustained epidemic experience began in 698 and ricocheted through the islands during the following fifteen years; the disease returned again in 735–37; yet again in 763–64; and twenty-six years later, in 790, “all males and females under the age of thirty were afflicted.” Periodic records of the return of this disease continue until the thirteenth century. Then it became a children’s disease (first so described in 1243), having at last achieved permanent lodgment within the Japanese islands.
⁸⁷

Dates for the introduction and eventual lasting establishment of other infectious diseases in Japan are not so clear. A new disease from which “over half the population perished” arrived in 808. By analogy from the evidence of the probable spread of plague along the China coast between 762 and 806, it seems at least possible that this was an irruption of bubonic plague into Japan, although absence of clinical description makes the identification merely a guess. In 861–62 yet another new disease—the “coughing violence”—hit the islands, and recurred again in 872, and in 920–23, with heavy loss of life. Mumps (whose distinctive swelling makes it a disease easy
to recognize in ancient texts) appeared in Japan in 959; and recurred in 1029. In 994–95 another disease struck in which “over half the population died.” If such a statistic is anywhere near the truth, such a heavy mortality must also have been the result of an unfamiliar infection encountering a virgin population. The measles record is also of interest. The modern term used for measles appears for the first time in 756, but serious and repeated epidemics so named began only in the eleventh century (1025, 1077, 1093–94, 1113, 1127). It was first mentioned as a childhood disease in 1224—thus anticipating the date at which “smallpox” achieved a similar status by a mere nineteen years.

Such records show that the Japanese islands pretty well came abreast of the disease patterns of China (and the rest of the civilized world) during the thirteenth century. For more than six hundred years prior to that time, however, Japan probably suffered more from epidemics than other, more populous, and less remote parts of the civilized world. As long as the island populations were not sufficient to enable such formidable killers as smallpox and measles to become endemic childhood diseases, epidemics of these (and other similar) infections coming approximately a generation apart must have cut repeatedly and heavily into Japanese population, and held back the economic and cultural development of the islands in drastic fashion.