Plagues and Peoples (18 page)

Nevertheless, the development of court life in southeastern Asia sustained trade in much the same way that the emergence of barbarian chieftains around the shores of the Mediterranean had sustained the trade patterns supporting urban civilization in that
environment. There
was
one
important difference, however. Food staples did not figure importantly in the trade of the southern seas, as was the case within the Mediterranean. Urban and court populations of southeastern Asia depended, as elsewhere in that continent, on food collected as rents and taxes from peasants living relatively close by, i.e., mainly upriver.

The development of this vast, if
loosely
reticulated, trade net across the southern seas was signalized by the arrival in China of “Roman” merchants in
A.D
. 166. They styled themselves ambassadors from Marcus Aurelius, and though their gifts were less impressive than the Chinese chronicler thought fitting, the event was nonetheless sufficiently out of the ordinary to have been officially recorded at the Han court.
⁴⁸
An even more convincing demonstration of the scale of trade during the first two Christian centuries was the excavation in 1945–48 of a trading station on the coast of southern India near modern Pondicherry. Roman merchants established a trade base there in the age of Augustus (d.
A.D
. 14), and seem to have occupied the site until about
A.D
. 200.
⁴⁹
This archaeological discovery backs up the remark of the geographer Strabo (ca. 63
B.C-A.D
. 24) to the effect that trade with India had assumed a much enlarged scale in his own time.
⁵⁰

During the two centuries that followed the beginning of
the Christian era, therefore, it seems certain that trade between the eastern Mediterranean, India and China operated on a regular basis and attained a scale that dwarfed all earlier exchanges across such distances. Caravans passed overland across the oases and deserts of central Asia by regular stages, while ships traveled freely across the Indian Ocean and its adjacent waters.

Regular movement to and fro across such distances implied exchange of infections as well as goods.
⁵¹
Chances of an unfamiliar infection spreading among susceptible populations certainly multiplied, and there is reason to suppose that before the end of the second century
A.D
. epidemic disasters in fact struck severe blows to Mediterranean populations, and probably afflicted the population of China as well. In between, nearer the center of the web of civilized life in the Old World, signs of disastrous population decay arising from unaccustomed exposure to lethal epidemics do not seem to exist. Either the populations of Middle Eastern and Indian cities had little to fear from diseases previously established among the Chinese and Mediterranean populations, but did have diseases of their own to export with lethal effect; or surviving records are so imperfect that disease disasters in Middle Eastern and Indian landscapes cannot now be detected.

Indirect evidence suggests that exposure to new infections had little effect in either India or the Middle East. In Mesopotamia, for example, a survey of ancient canal systems concluded that population crested between
A.D
. 200 and 600, just in the age when epidemics were cutting deeply into Roman and Chinese populations.
⁵²
In India, the political consolidation and cultural efflorescence of the Gupta age (
A.D
. 320–35) also suggests (though scarcely proves) that no particularly severe demographic disasters afflicted that country as a result of the merging of previously separate disease pools in the first Christian centuries.

It is easier to understand this seemingly contradictory situation if one remembers how little effect the disease circulation created by the opening of the oceans after
A.D
. 1500 had on
Europe, where the ships and sailors responsible for the new patterns of disease circulation were at home. Lisbon and London became infamous for the fevers and fluxes ships occasionally brought back from foreign shores, but western Europe as a whole was scarcely affected, even though millions of Amerindians and other vulnerable peoples were suffering catastrophic die-offs. By the sixteenth century, clearly, Europe had much to give and little to receive in the way of new human infections. In the first Christian centuries, however, Europe and China, the two least disease-experienced civilizations of the Old World, were in an epidemiological position analogous to that of Amerindians in the later age: vulnerable to socially disruptive attack by new infectious diseases.

The Roman world assuredly met serious epidemiological disaster between the second and sixth centuries
A.D
. Roman data, however scant, are far better studied than is the case elsewhere, and it therefore seems best to survey the disease record of Europe in the centuries following the establishment of regular transport across Eurasia before considering what took place in other parts of the world.

Outbreaks of disease were, of course, nothing new in Roman history in the second century
A.D
. Livy records at least eleven cases of pestilential disaster in republican times, the earliest dated 387
B.C
.
⁵³
Another epidemic struck the city of Rome in
A.D
. 65, but these experiences paled before the disease that began spreading through the Roman empire in
A.D
. 165.
⁵⁴
It was brought to the Mediterranean initially by troops that had been campaigning in Mesopotamia, and dispersed generally throughout the empire in the following years. As usual, it is not possible to identify this “plague” definitely with any modern disease, though smallpox (or a disease ancestral thereto) has often been suggested.
⁵⁵
The disease remained epidemic for at least fifteen years, breaking out in different places from year to year and returning sometimes to cities previously affected.

Despite the scanty evidence, it is reasonable to conclude
that the disease was new to Mediterranean populations, and behaved as infections are wont to do when they break in upon virgin populations that entirely lack inherited or acquired resistances. Mortality, in other words, was heavy. In affected places, probably as much as a quarter to a third of the entire population died.
⁵⁶
Since such a disease is unlikely to reach every populated place, the population of the empire as a whole did not diminish so sharply; the over-all loss, however, was definitely noticeable. What mattered even more was the fact that this episode inaugurated a process of continued decay of the population of Mediterranean lands that lasted, despite some local recoveries, for more than half a millennium.
⁵⁷

One reason for the continued decay of population within Roman borders was that fresh outbreaks of serious
pestilence
continued to occur. A new round of a magnitude fully comparable to the Antonine plague of 165–80 hit the Roman world in 251–66. This time reported mortality in the city of Rome was even greater: five thousand a day are said to have died at the height of the epidemic, and there is some reason to believe that rural populations were affected even more sharply than in the earlier epidemic years.
⁵⁸

As in the case of the Antonine plague, there is nothing in existing records upon which to base an exact identification of the disease (or diseases) that ravaged Roman populations in the third century. Nevertheless, there are some suggestive circumstances that make it tempting to believe that these two demographic disasters may signalize the arrival among Mediterranean populations on an ongoing basis of the two most formidable of our familiar childhood diseases, i.e., measles and smallpox. As we have seen, the evidence of Hippocrates seems to show that no such diseases were known in his time. But by the ninth century
A.D
. when the Arabic physician al-Razi (850–923), who worked in Baghdad, gave the first unambiguous clinical description of these afflictions, epidemic diseases involving skin rashes were of immemorial familiarity in Near Eastern lands.
⁵⁹

If one looks for earlier mentions of fevers with skin eruplions,
the most notable passage occurs in Gregory of Tours, who mentions an epidemic in southern France in the year 580 that involved skin rashes of some sort.
⁶⁰
Before that, texts are vaguer, though various other references can be interpreted as referring to skin eruptions in connection with epidemic outbreaks. The great doctor and influential medical writer, Galen, actually lived through the Antonine “plague,” but he is not very helpful. Galen classified the disease ás an abscess of the lungs, because spitting blood seemed a far more important symptom to him than mere spots on the skin. Still, in several passages he refers incidentally to epidemic outbreaks of fever together with pustules, but his humoral theory of disease made such symptoms insignificant. His phrases therefore remain tantalizingly imprecise and resistant to conclusive modern diagnosis.
⁶¹

By the sixteenth century, when European medical writers finally recognized that measles and smallpox were distinct diseases, there is no doubt that both had become standard childhood afflictions, familiar in all parts of the continent, and of considerable demographic significance, inasmuch as many children died of one or the other, with or without additional infectious complications. The literary record therefore points to the second to third centuries
A.D
. as the most probable time for these two diseases to have established themselves among Mediterranean populations. The sequence of two devastating pestilences, the first coming between
A.D
. 165 and 180, and the second raging from
A.D
. 251 to 266, is exactly what one would expect—indeed what was required—if, one after the other, these two highly infectious diseases broke in upon the comparatively massive but previously unexposed populations of the Mediterranean world.

No satisfactory estimate of over-all population loss can be made. It must have been very high, though, for disease was not the sole factor attacking Mediterranean populations. Beginning in 235, civil disorders and barbarian invasions spread destruction far and wide within Roman frontiers, and famine not infrequently followed. Agreements allowing barbarian
tribesmen to settle within Roman frontiers in return for some sort of agreed military service began in the second century and multiplied in later times. This in itself is indication of empty or near-empty land that could be assigned to immigrants without displacing Roman taxpayers and potential recruits. Even more telling was the series of laws, beginning in the time of Diocletian (reigned 285–305), that prohibited cultivators from leaving the land and made a number of other occupations hereditary and obligatory. The object of such laws was to compel the population to provide services required for maintenance of the imperial administration. Obviously, the only reason for such legislation was persistent shortage of persons able to perform the required functions voluntarily.

One must, then, imagine prolonged population decay resulting from intensified micro- and macroparasitism within the Mediterranean lands. Even in the first century
A.D
. after the Augustan peace had ended the destructive civil wars, there were some parts of the empire—Greece and Italy particularly—that failed to prosper. The Roman imperial system collected tax moneys from lands close to the sea and transferred spare cash to the armies stationed at the frontiers. This remained a viable arrangement (though Augustus and other emperors often found it difficult to meet the military payroll) until the heavy blow of unfamiliar disease seriously eroded the wealth of the Mediterranean heartlands between
A.D
. 165 and 266. Thereupon, rapid die-off of large proportions of the urban populations at the most active centers of Mediterranean commerce diminished the flow of cash to the imperial fisc. As a result, pay for the soldiers at accustomed rates could no longer be found, and mutinous troops turned upon civil society to extract what they could by main force from the undefended landscapes which the Roman peace had created throughout the empire’s Mediterranean heartlands. Further economic decay, depopulation, and human disaster resulted.

Military uprisings and civil wars of the third century
A.D
. quickly destroyed one set of landlords—the
curiales
—whose
rents had sustained the outward trappings of Greco-Roman high culture in the empire’s provincial towns, but a new and more rural landlord class, often enjoying partial immunity from imperial taxes, arose almost at once. Insofar as this arrangement prevailed, the hard-pressed peasant population of the empire, by submitting to a local landlord’s demands for goods and services, escaped the older jeopardy of owing rents and taxes to different authorities, but it is doubtful whether the over-all pressure upon cultivators was significantly reduced. Rather, by channeling more into the hands of local potentates, resources at the command of the central administration diminished, and the empire became more vulnerable to external attack. The upshot, as is well known, was the breakup of the imperial fabric in the western provinces and its precarious survival in the more populated east.

Historians have traditionally emphasized the macroparasitic side of this balance. This accords with the tenor of surviving sources, which allow a reasonably exact reconstruction of the wars, migrations and flights that resulted in the fall of the Roman empire in the west. Yet, the ravages of armies, and the ruthlessness of rent and tax collectors—great though these certainly were—probably did not damage Mediterranean populations as much as the recurrent outbreaks of disease, for, as usual, disease found fresh scope in the wake of marching armies and fleeing populations.