“What do you mean?” Kate asked.
“In the wake of the plague, we see the end of the supercities of the ancient world. Ancient Persia, once a super-nation, crumbles. The Eastern Roman Empire had been close to retaking its western half—the ‘Rome’ everyone talks about. But in the wake of this pandemic, it’s besieged and almost falls. It eventually becomes the Byzantine Empire. We see these falls across the world—mighty empires recede and barbarian tribes actually gain ground. The major lesson from the Plague of Justinian is that the most connected civilizations, the most advanced, those with established international trade routes and supercities: they suffered the most. It was the isolated, simple societies that fared the best. Take sixth-century Britain—it’s a great example. Britain at the time of the plague was dominated by the Romano-British. Based on artifacts, we know they traded with nations as far away as Egypt—that’s where the plague first appeared, by the way, or that was the first account.”
“I don’t understand,” Dr. Chang said.
“The trade routes brought the plague. The British had been at war with several Germanic tribes that had settled their western coast. At the time of the outbreak in the mid-sixth century, these tribes were mostly contained and regarded as barbarians. No one traded with them, and the British mainly refused to intermarry with them. In the wake of the outbreak, these tribes seized the initiative, spreading throughout Britain and eventually taking control. The primary tribes were the Angles and the Saxons. In fact, some believe the legend of King Arthur is a composite of British knights who fought these Angle and Saxon invaders. The fact that people in Britain and around the world speak English—a Germanic language—is because of the plague… and the Angle and Saxon triumph after. It wasn’t just Britain, this happened around the world: advanced civilizations, with cities and population density and established trade routes, fell. The barbarians beyond their gates rose, invaded, and most of the time, just moved on. In cases where the barbarian invaders set up their own government, they were usually sacked a century later by the next roving band of raiders. This was the real end of an era, a time of great cities and civilizations. The Dark Ages came after and they lasted for a very long time—almost a thousand years. It was the greatest reversal of progress in history. In fact, the Dark Ages only really ended after the next major outbreak—”
“Hold on,” Kate said. “I have to confess my ignorance here. I’m a geneticist. I just don’t see how a volcano and a volcanic winter are connected to the Plague of Justinian.”
David smiled. “I can’t believe I’m about to explain a scientific concept to you.”
“Let’s just see how good your explanation is,” Kate shot back.
“Part of history is tracing artifacts and looking at patterns. One pattern that emerged from the outbreak is that it began in northern Africa, moved into Egypt, and from there, exploded into the eastern Mediterranean. Once it hit Constantinople, the rest of the modern world fell like dominos as trade ships carried the plague around the world. There’s still some debate, but many historians believe that the plague came to Europe on grain barges from northern Africa, and that it was the rats on the barges that initially carried the disease.”
“What David says is true,” Dr. Janus said. “It is a great irony: the real danger from rapid climate change has nothing to do with the weather. The danger is destabilizing ecosystems, causing organisms that normally have no interaction with each other to come into contact. We know that most outbreaks are caused when wild-animal reservoir hosts, that benignly harbor a deadly pathogen, are forced out of their natural habitats. In the wake of this second ‘Toba volcano,’ ecosystems around the world were destabilized. If Dr. Grey’s theory is correct, it is incredibly intriguing. The ancient world would have been a very difficult place to manage a global genetic change. A plague is the perfect vehicle, but there remains one very big problem.”