POSSIBLE
IMPLICATIONS
Conceptually,
relating climate change and agriculture is a simple process.
If a pre-industrial farming practice fails or does not produce enough
sustenance then more land is cultivated. If
there is no more available land then migration is an option (Salvesen,
1992)
. If this simple process is
complicated by climate change, the process can become extreme or occur more
rapidly. The tree-ring record of
the 3rd and 4th century implies that this period was
complicated by climate change and as Huntington puts it “when the plains began
to grow rapidly drier, the inhabitants [the Huns and Ostrogoths] must have
suffered sorely” (Huntington,
1907)
.
Archaeological
evidence supports the presence of bones of cattle, pigs, and sheep used for food
sources. At almost every
archaeological site, evidence of weaving and dairy production is present.
Seed for spelt, emmer, wheat, lentils, peas, fruit and berries have all
been found in containers and residues at various sites around central Europe (Wells,
1999)
. The evidence of the
dependency of the Germanic tribes on agricultural products for their livelihood
is very strong.
This basic
knowledge is essential in understanding how it could be possible for prolonged
drought periods to significantly affect the indigenous tribes of Germania.
King Filimer of the Goths could have left Germania in AD 150 due to an
extended ten-year drought period. The
year he returns to Germania is a prosperous year.
This is where the argument may or may not be speculative.
However, it is interesting that King Filimer and his Goths moved at the
end of a long drought period, which surely would have caused food stresses among
the tribe. Even though it is not
possible to prove causation, it is easy to understand that a ten-year drought
period affected these tribes.
These added
environmental stresses evident in paleoclimate proxies could have played an
important role in the motivations in the movement and invasions of the Germanic
tribes. The division of the Goths
into the Ostrogoths and Visigoths occurred in the third year of a fourteen-year
below average period. This could be
a reflection of the environmental stresses.
In AD 230, the Ostrogoths stopped their migration and settled near the
Slavic tribes in the first and only good year in a nineteen-year poor period.
With the knowledge of the climatic conditions the question must be
raised, “Do the Ostrogoths settle in this year for no reason or because this
is the first year in sixteen years that is suitable for both agriculture and
livestock?”
All of the 3rd
and 4th century AD events of the abridged timeline in the previous
chapter could have arguably been attributed to climate change 81.4% of the time.
However, the possibility of humans reacting and behaving in ways that are
contrary to mathematical numbers is ever present.
Climate studies such as this one do not imply that climate is the only
factor in the decision making process of the tribal leaders in Germania, but
merely suggest that climate data should be considered.
The
events of AD 238 are numerous and there are many incursions into the Empire.
This is one of the first major attacks on Roman limes
and occurs in the third of three consecutive poor years.
Another three-year poor period occurs from AD 250 to 252 and there are
major migrations, invasions, and Emperor Decius is killed.
These events have often been attributed solely to the violent,
bloodthirsty nature of the Germanic tribes.
However, with these events occurring in predominantly drought periods,
could the aggression and will to look elsewhere for new lands be attached to the
lack of agricultural productivity in their homelands?
Climate is
usually studied during drought periods, however, prosperous periods also play a
part in the 3rd and 4th centuries AD.
These good periods can also contribute to the motivations of indigenous
tribes. In fact, after the long
periods of below mean growth in the tree rings of the first part of the 3rd
century, the above mean periods could have helped to fuel the continued attacks
in the mid 3rd century. The
few years before Postumus’ seizing control of Gallia, AD 260, where the best
years of the third century. However,
two years after 260 a nine-year poor period may have made controlling Gallia a
little more difficult.
This long
poor period may have hindered the Roman Empire by reducing the frontier
soldiers’ food stores and inducing the Germanic tribes to move.
In AD 279, when the tree ring chronology implies a beginning of a good
period, the Burgundians return to Germania and settle.
Again, the changes in climate, once known, may assist in an understanding
of the tribes that would not be a supportable inference without the tree-ring
data.
Other
inferences, such as the Edict of Prices by Diocletian in AD 301, are made at the
end of poor periods and may reflect the depressed agricultural economy that
would accompany an eight-year poor period.
The drought recorded by Sozomen, a Byzantine writer, in AD 348, is in the
fourteenth year of a twenty-year poor period evident in the tree-ring record.
The Visigoth king, Athanaric, ordered that a statue of Nerthius be
carried in her wagon through the Christianized Goths because of this drought.
Nerthius was among the Germanic tribes’ pantheon representing the
earth. This goddess’ abodes where
lakes and groves occur and she was believed to influence the fertility of the
earth. This is why king Athanaric
forced the Visigoths to worship her and not the Christian God (they had been
converting to Christianity in AD 341). Athanaric
credits the drought as being the fault of the populace for no longer worshipping
Nerthius and her, in turn, cursing them.
AD 357 is
documented as a very prosperous time and the tree-ring record shows this year as
the 4th of a twelve-year good period.
These documents state that both Swabia and Dacia were prospering
agriculturally. AD 359, also in
this twelve-year good period, sees the Burgundians settling in Rhone and Swabia
and developing economic ties with Rome. These
two years validate the tree ring record over 1500 years ago by correlating
exactly with the documentation.
The
nineteen-year poor period (AD 364 to 383) may have been a contributing external
factor, among the multitude of internal reasons, to the welling attacks against
the Roman Empire. The Goths invade
in AD 364, the battle of Catalonian Fields is in 366, the Huns and Alans attack
in 370, Saxons attack in 371, the Huns and Goths move 372, the limes
are attacked several times in 373, the Goths, Quadi, and Burgundians attack in
374, Huns, Alans, and Goths attack in 375, major attacks on the limes
in 376, the Goths attack in 377, Emperor Valens is killed in 378, and the
frontier is held in 379. This is a
very active period with many different tribes repeatedly attacking Rome.
The fact that these incursions all occur in a below mean period as
evident in the tree ring record at least merits consideration.
The fact
that the Goths declare war on Rome in AD 369 because they are banned from
trading in foodstuffs is not surprising in an environmentally stressed period. AD 369 is the only above mean year in this nineteen-year
below mean period. Agriculturally,
this would be the first productive year since 364 AD for both the Goths and the
frontier Romans. Denying trade in
the first year that trade would have been possible would be a tremendous insult
to the Goths, as there would be evidence of adequate crops in the marketplace.
The Goths, in turn, declare war on Rome not just because they were denied
trade, but possibly because it seemed that the Romans were hoarding foodstuffs
and leaving the Goths to fend for themselves.
The next
below mean period is AD 399 to 405. Alaeric
and the Goths begin to attack the decaying infrastructure of the Western Roman
Empire. Some of these coincidences
of drought and prosperity are probably just coincidences, but some favor
causation. The 3rd and 4th
centuries AD are a climatically turbulent time and definitely affected the
Germanic tribes in varying degrees.