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386 13. specialized production and exchange
and hence also military, muscle? And did subsequent economic decline in
the east help cause the military problems of later-sixth- and seventhcentury
Byzantium? It is important to bear these possibilities in mind and
to continue to investigate them – even if, at present, the data (particularly
relating to the western and later eastern military collapses) tend to be too
hazy to provide any firm answers. For instance, it is not yet clear whether
we can confidently identify widespread economic decline in the western
provinces (which included a seemingly very rich Africa) before the great barbarian
incursions of 406.
xi. climate, the environment and the economy
As well as warfare, climatic change or environmental change is sometimes
blamed for the decline of the Roman economy. Climatic change at this date
was an ‘act of God’, unaffected by man, while environmental change could
be caused either by changes in the weather or by the human impact on the
landscape. 69
Strangely enough, despite its importance in present-day environmental
debate, climatic change is not currently much favoured as an overall reason
for Roman economic decline. 70 It would, indeed, be very difficult to find a
change of climate that could explain the extraordinary and localized
fluctuations of wealth visible between the fourth and the seventh century.
What change in climate could have benefited Ireland, Armenia and the near
east in the sixth and early seventh century, while at the same time devastating
Britain, Italy and Asia Minor?
Even looking at highly marginal areas, which must be the first to be
affected by any change in climate, changes in human activity, rather than
broad changes in the weather, often provide more plausible reasons for
fluctuations in settlement and wealth. The dry semi-desert of the Negev
was, as we have seen, densely settled and prosperous in the fifth and sixth
century, which might be explained in terms of a period of exceptional rainfall.
However, in this same period, the closely comparable wadis of
Tripolitania (in modern Libya), which were prosperous and densely settled
at an earlier date (the later first and second centuries a.d.), seem to have
been largely abandoned. Since the Libyan pre-desert and the Negev must
share roughly the same climate, and since they were certainly exploited in
very similar ways, their very different histories strongly suggest that it was
human opportunity and human pressure that most influenced these two
marginal regions, rather than some external change in the weather. 71
69 For a useful brief discussion of the issues raised in this section, with further references: Greene
(1986) 81–6.
70 The issue is, however, debated in relation to specific regions: see e.g. Rubin (1989) for the Negev.
71 For Libya: Mattingly (1995) 144–53.
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