a. Of or relating to the ancient city of Byzantium.The way I was taught the history of the Fall of Rome in high school could be summed up in two sentences: Rome (the Western Empire) fell in 472 when the Goths came over the hills. Constantinople (the Eastern, or Byzantine Empire) lasted another 1000 years, until the Turks took it in 1453. The real picture, fittingly, is much more complicated, intricate, and involved than that.
b. Of or relating to the Byzantine Empire.
c. Highly complicated; intricate and involved.
I wrote last week that there was some merit to thinking about a "Byzantine scenario" where parts of the global economy collapse, while other parts do relatively well. Just in time, I finished reading The Coldest Winter, David Halberstam's book on the Korean War, and picked up The Inheritance of Rome where I'd left it -- the beginning of Chris Wickham's chapters on the Eastern Empire. What's clear, even from Wickham's survey account of Byzantine history, is that there's actually little solace to take: it turns out it's actually quite difficult to maintain the functions of your state while the international order is collapsing. But let me get to that in a minute.
What caused the Fall of Rome in the West? Well, if you're an anthropologist like Joseph Tainter you can argue a number of historical structural trends converging in the late 5th century make the complexity of Roman society unsustainable. If you're Richard Nixon, you blame the gays. Wickham argues that, at the beginning of the 400s, there was actually little reason to believe that Rome was approaching the end of days: the Crises of the 300s were behind it, the state was functioning moderately well, and an observer without the privilege of knowing how it all turned out could be forgiven for not guessing what was coming. (Remember Namantianus!) Wickham's entire book is devoted to avoiding the trap of seeing the events of the past as prologue for the present: these things happened for their own reasons, with actors involved pursuing their own interests, and not because they were fated to or because there was something better waiting to happen in the future.
Wickham argues that what really caused the collapse of Rome in the West is quite prosaic: the Vandals, having moved through Italy into North Africa, declined the honour of providing Rome with free grain, as the African provinces had for centuries. This sudden shock to the Roman system leads to a precipitous, and not at all surprising, decline in both tax revenues (the tax in this case being grain itself) and people choosing to live in Rome itself. This all happens in the 440s, and Rome never really recovers.
The seizing of the African provinces was as much a problem for the Eastern Empire as it was for the west though. As it became clear that Italian Romans (as opposed to the Byzantine Romans) were unable to recapture Carthage and the other rich provinces of North Africa, the Eastern Empire moved. The Emperor Justinian sent his armies west, and his General Belisarius recaptured North Africa and moved across the sea to take back Italy. Between 533 and 550, the Byzantines were rebuilding the Roman Empire with Constantinople the new core. By 550, the Empire looks very familiar:
It's basically the Roman world save France and the bulk of Spain.
Alas, it was not to endure. Various new kingdoms existed in France and Germany, all of whom were willing to fight to take a chunk of Italy back from the Byzantines. The Roman structures had collapsed so thoroughly that it was impossible to put them back together in any sustainable fashion -- though Wickam doesn't present any evidence that the Byzantines tried to do that. They weren't looking to rebuild a powerful Rome, they wanted the centre of the world to stay in Constantinople. Meanwhile, in the North, South, and East, Byzantium's borders were being threatened by any number of invaders. First the powerful Persian Empire in the east fought for control of Mesopotamia and Syria, and briefly held Jerusalem but was eventually defeated in an early example of, er, a Crusade. Just as soon as the Persians were beaten, the up and coming Arab armies swung through Mesopotamia, Syria, Egypt, and North Africa and absolutely devastated Constantinople's tax base and its ability to feed itself.
Within a century of the Empire's height under Justinian I, the city of Constantinople would see its population cut by 3/4, and it was sacked by Arab armies between 674 and 678. (It's a mark of how the Mediterranean world had collapsed, that even at 25% its previous size Constantinople was still the largest city in Europe.) The economy of the Byzantine region collapsed, and between 700 and 800 or so it seems like there was precious little coinage minted. Armies were localized, and the Empire was geared entirely towards self-defense. What tax there was, was raised in kind. Armies were paid with food, not money. What happened first in Rome, came later in Constantinople, but the results were the same: cut off from the richest source of revenue, the empire suffered demographic and economic collapse. The only difference is that in the East, the forms of the state continued, albeit radically different.
Of course, food isn't just revenue: it's energy. What happens to societies when the richest, lowest-cost sources of energy they've been using to subsidize the structures of power and finance collapse? It's worth pointing out that the Vandals were willing to sell the grain to Rome -- they just weren't willing to give it away as Rome had expected for so long. All that occurred, in modern terms, was that Rome would have to pay the real, unsubsidized cost for the energy it needed.
Oil is the obvious thing to compare to food here, but another good one would be food: Americans eat massively subsidized, protected food that is physically dependent on increasingly-precious oil and increasingly-precarious federal finances. And even with all this support, America suffers with some of the highest levels of working poor in the developed world. While on average Americans could afford to pay more for food, the reality is that the continuing inflation in food prices is making malnutrition a real mass concern. Both of the struts that support the American food supply are imperiled, and America could really use a Belisarius of some kind to help keep its system in check.
The problem is that not every society is fortunate enough to have a Belisarius when they need one.