Chapter 2: Europe in the Middle Ages

Europe was (rightly or wrongly) considered the backwater of the civilized world for most of history. So how is it the Europeans built global empires and changed the world with industrialization?

In this 25-minute episode, I’m going to run through the developments of the Middle Ages and the circumstances of life in Europe that gradually led to a new world order. Topics include:

  • The impact of Ancient Rome

  • The Dark Ages

  • The Crusades

  • The Black Death

  • Trade with the Islamic World

  • The early days of modern finance

  • The rebirth of learning and practical inventions

Sources for this episode include:

Asbridge, Thomas. The Crusades: The Authoritative History of the War for the Holy Land. HarperCollins. 2010.

Diamond, Jerad. Guns, Germs and Steel: The Fates of Human Societies. W.W. Norton & Company. 1997.

Ferguson, Niall. The Accent of Money: A Financial History of the World. Penguin Books. 2008.

Frankopan, Peter. The Silk Roads: A New History of the World. Vintage. 2015.

Herreld, Donald J. "An Economic History of the World Since 1400." The Great Courses. 2016.

Johnson, Steve. How We Got to Now: Six Innovations That Made the Modern World. Penguin Random House. 2014.

Satia, Priya. Empire of Guns: The Violent Making of the Industrial Revolution. Penguin Press. 2018.

Seife, Charles. Zero: The Biography of a Dangerous Idea. Viking Press. 2000.

Full Transcript

One thing I do not want this podcast to be accused of is Eurocentrism. But avoiding the appearance of it is quite difficult because the Industrial Revolutions do start in Europe, and I have to explain how and why.

And “why Europe?” is a particularly good question. Because for most of human history, Europe was (rightly or wrongly) considered the backwater of the quote-unquote civilized world. But beginning in the late Middle Ages, a series of developments would lead the Europeans to establish global empires. And then, change the world forever with industrialization.


This is the Industrial Revolutions.

Chapter 2: Europe in the Middle Ages.


Last week, we left with a brief overview of how agriculture and inventions left the Fertile Crescent for the rest of the Eurasian landmass. And Europe was in dire need of what the Fertile Crescent had to offer. The climate in most of Europe is harsh, and the land isn’t very productive. But thanks to the cattle and horses they were getting from the east, Europeans were able to start plowing the earth for farming. They developed seasonal planting and harvesting patterns to get the most out of the soil.

Things were easier in the Mediterranean, where flourishing societies began to spring up along the coasts of the Aegean Sea, including Greece. This was during an age of empires in the Middle East, including the Egyptians, Babylonians, and Medians, who we often call the Persians. Alexander the Great came out of northern Greece to eventually conquer them all.

But Alexander had relatively little interest in the rest of Europe, which was still pretty uncivilized. Nevertheless, there were traders in Greece and the eastern Mediterranean who decided to see what-was-what out west, and they set up a few outposts.

Soon enough, one tiny community in the west did grow quite big: Rome.

How big? At its greatest extent in 117 AD, the year the emperor Trajan died, Rome controlled some amount of land in the following modern-day countries and territories:

England, Wales, the Netherlands, Germany, Luxemburg, Belgium, France, Monaco, Andorra, Spain, Portugal, Morocco, Algeria, Tunisia, Libya, Egypt, Sudan, Palestine, Israel, Jordan, Saudi Arabia, Syria, Lebanon, Iraq, Iran, Kuwait, Azerbaijan, Armenia, Georgia, Turkey, Cyprus, Russia, Ukraine, Moldova, Romania, Bulgaria, Greece, Macedonia, Albania, Kosovo, Serbia, Montenegro, Bosnia & Herzegovina, Croatia, Slovenia, Hungary, Austria, Lichtenstein, Switzerland, Malta, San Marino, the Holy See, and of course, Italy.

For the record, that’s 53 modern-day states.

And the Romans had left their mark across this empire in some important ways. Among them, they introduced a client-patron ethos onto the agricultural system of Europe. The relationship between landowner and tenant farmer would serve as a model for the Middle Ages.

But Rome got too big, and the imperial bureaucracy couldn’t manage it forever. So, the emperors appointed co-emperors and then junior emperors to help manage the affairs of the four quadrants of the giant territory. And in theory, one co-emperor was supposed to come to another’s aid when he needed military support. And they found they were able to pull off this arrangement, just so long as there was no huge rush of threats from the outside.

But by the turn of the fifth century, you guessed it, there was a huge rush of threats from the outside.

During the 300s, severe weather patterns on the plains of Central Asia caused a great deal of fauna there to die. The herds of game there depended on the fauna for food. As a result, the local, horse-mounted, nomadic tribes hunted the herds too thin. The tribes needed to head west now for new hunting opportunities, and they were perfectly happy pushing the western inhabitants off their lands.

These tribes are known to us today as the Huns.

The Huns weren’t the tribe that posed the immediate threat to Rome, it was the tribes the Huns were pushing farther west. The Goths pushed into the Balkans. The Visigoths sacked Rome, as did the Ostrogoths later on. The Vandals made their way down to Spain, into North Africa, up to Sicily, before sacking Rome. The Franks and Angle-Saxons invaded Gaul and southern Briton, respectively, which is how those places became known as France and England.

By the time the Huns arrived in western Europe, led by Atilla, the western Roman Empire had dissolved.

In its place was a messy quilt of small chiefdoms. Without strong, central government, the chiefs’ warriors filled the void and protected the local population. But the chiefs didn't have a lot of treasurer at their disposal. So, like a tech start-up paying employees in stock rather than liquid cash, they granted land to their warriors, which (after all) would pay off more in the long run. A system of vassalage was developed.

It happened in a 500-year period we call the Dark Ages, because the historical details are sketchy – largely because few Europeans could read or write anymore. But we know the little chiefdoms went through a process of war and amalgamation to become the Medieval kingdoms of Europe. The warriors became Counts and Dukes, the chiefs became Kings. Helping stir the pot during these years were constant Viking invasions across the continent.

Today we might think of the Viking invasions as a sort of theft. They came in, setting up little Viking kingdoms, stealing lands that didn’t belong to them. But our idea of land ownership at this time would have been a strange one. A king controlled the land and he granted it to one of his dukes or counts or knights. That guy would collect a share of the crops or treasure from the farmers on that land. But nobody really owned it in the way we think of property rights today.

On a more macro-level, that meant there was no such thing as a modern state. It was a realm. In the immigration debate today, we often hear about this idea of open borders, and someone will inevitably say something like “a country without borders isn’t a country at all!” or “Since the beginning of time, countries have always had borders.” But this isn’t even remotely true. Just like property rights, the idea of states with clearly-defined borders is a relatively new thing, developed in the years between the end of the middle ages, and the start of the first industrial revolution.

That’s not to say immigration was an option in those days, but it wasn’t because of a citizenship issue. It was because you were tied to the land. Leaving it meant you were leaving your work, which you needed to do to pay rents to your lord. You couldn’t just up and abandon your lord. You didn’t have that right back then.

Now, when the tribes overthrew the Romans, they weren’t just overthrowing the administrative state, they were overthrowing the state religion too: Christianity. That belief system sprang back into action during the Dark Ages, though, with its leaders hell bent on converting the new kings and their followers.

And when explaining how Europe fell into disarray during these years, the scholars in the prosperous Middle East pointed the finger at Christianity. They argued, the Greeks and early Romans had cared about math and philosophy. But when they converted to Christianity, Europeans were no longer interested in learning. The same snobbish, cultural superiority argument we see westerners make today was actually hurled against westerners for most of history. Western European lands were such backwaters, as one Islamic scholar put it, “we did not enter them [in our book] because we see no use whatsoever in describing them.”


But western Europe and its Latin church did give Islam cause for concern around 1100 when an army of nobles and knights marched into the Levant and sacked Jerusalem. If the westerners wanted to prove Islam’s cultural superiority wrong, boy did they miss the mark. The actions of the Crusaders, according to the Crusaders’ own accounts, were shockingly violent and… just gross.

The Islamic world, at this time, was caught in a power struggle between competing Shiite and Sunni caliphates. So after the Crusaders reclaimed the holy city (and presumably drained out all the blood from the streets that literally stood above their ankles) they set up new Crusader states in the region that managed to last a century.

All alone in the Holy Land, the Crusaders needed supplies from back home. And so, a trader-merchant class burgeoned in the port cities of the Italian peninsula. Traders in these cities had been around forever, especially thanks to the Viking river traders moving goods and slaves south to the Middle East in the centuries before. But now they were making regular trips to the Levant and increasingly to Egypt too.

Even after the unifier sultan Saladin put an end to the Crusader states, the trader-merchant classes remained. And they had set up networks with the Muslims who sat at the center of global trade.

This was important for three reasons.


The first was an inadvertent import they brought to western Europe: The Black Death.

The three strains of the disease – bubonic plague, pneumonic plague, and septicemic plague – had developed in Central Asia and made its way to China in the 1330s, before heading west up the silk roads. By the time it reached Constantinople in 1347, it had killed about 25 million people in East Asia, including at least half the population of China.

The disease was spread by fleas. They were carried by rats that had snuck onto Genoese ships back to Italy. After killing the rats, the fleas would have to find a new food source, which meant blood from another animal, such as a human. Italians start dying in huge numbers. This was way before modern science, and people had been dealing with the nuisance of fleas since forever, so they had no way of knowing how they were getting infected.

The Black Death quickly spread across Europe. Within a handful of years, it may well have killed one half of the western European population.

And it’s not like the years leading up to the Black Death had been easy. Several years of crop failures starting in the 1320s had already led to a lot of malnutrition, and crazy conflicts like the Hundred Years War had been disrupting economic activity.

But as awful as the Black Death was, it created a turning point for the social and economic structures of Europe.

For one thing, with so many people dead, the supply of the workforce was cut in half, meaning the value of labor had just doubled. Peasants were now in a bargaining position, and oh did they take advantage of it. Not only did they seek higher wages or lower rents, they wanted more freedom of movement and less indenturement. When the lords refused, it set off peasant revolts, and some pretty notorious ones are documented in histories of England and France.

At the same time, population thinning meant demand for food was cut in half. The price of grain fell sharply. Some farmland was simply abandoned and allowed to turn back into forest.

Before the plague, labor was cheap and land was valuable. Now it was the other way around.

Extreme poverty fell sharply. Demand for expensive foods like beef, cheese, and wine went up, and more and more, the gentry decided to focus on those things since they were less labor intensive. They also decided to use more of the open land for sheep grazing and wool production, which will have huge implications down the road.

And with their new freedoms of movement, a lot of peasants moved into the towns and cities around them, joining the forces of the urban crafts makers and their guilds.

Overall, it took about 150 years for the population of western Europe to return to pre-plague levels, and by that time, the effects of the plague were made permanent. Serfdom was nearing its end, and the Renaissance was in full swing.


When we think of the Renaissance, we of course think of the great arts that were developed in Italy, especially in Florence. Guys like Leonardo, Donatello, Botticelli, Michelangelo, all of whom got their commissions from one very powerful family: the Medici.

The Medici were products of the second reason why the Italian merchant trading was important, because it requires investment. It requires loans.

But in the middle ages, you couldn’t charge interest if you were lending money. That was usury, the church considered it a sin, and you would be excommunicated if you did it. And in those days, excommunication was not worth it.

But how do you encourage lending if nobody can make money from it? Well, there was a way around the usury laws: Play with the exchange rates.

Nowadays, every country pretty much operates on a single currency, but in those days, there were currencies for just about every city and town in Europe. So, what you could do if you wanted to buy and sell some perfumes from the Middle East to the European market? You could go to a local moneychanger and ask him for 100 units of currency A. With that money, you buy the perfume and sell it at a mark-up. Then you go back to the moneychanger and pay back the loan, interest-free, with 100 units of currency B. It just so happens that the exchange rate is favorable to the moneychanger, because 1 unit of currency B equals 1.2 units of currency A. Except, everybody knew that was going to happen going into the arrangement.

Not only does this undermining of the usury law help the flow of commerce, it also helps the development of modern business contracts and the development of modern finance. Without those things, we never get the industrial revolutions.

Oh, and the moneychangers could always be found sitting on a bench for some reason. The old Italian word for “bench” was “banca” and that’s where we get the words “bank” and “banking” from.

Modern banking actually started with the Crusaders themselves, and the orders they started, like the Templars. They had exemptions from the usury laws, which helped kick-start the new lending trend in finance.


And finally, Italian trade from the Islamic world led to perhaps the most critical development of the later Middle Ages, a rebirth of learning and a steady growth of invention.

Even before the Crusades, exposure to Islamic learning had started in Spain, where the Moors had pretty much completely taken over. During his formative years, Pope Sylvester II had spent some time in Barcelona, where he was exposed to a pretty ingenious system of Hindu-Arabic numerals. Those Europeans who could read and write at the time were still using old Latin numbers, like I, or V, or CLXIII. Sylvester was an early cheerleader of the new numerals, which made arithmetic and bookkeeping actually make sense. But his papacy was short-lived and his ideas were ahead of their time.

Hindu-Arabic numerals really start taking off because of a Pisan trader who set up connections in the north African port town of Béjaïa and brought his son, Leonardo, with him. Leonardo studied mathematics there using Hindu-Arabic numerals, and he grew up to be perhaps the greatest mathematician of the Middle Ages. We know him as Fibonacci.

In his book, the Liber Abaci, Fibonacci goes to great lengths to explain the Hindu-Arabic numeral system, and how it will make everybody’s life way easier. Not just bookkeeping, but conversions and calculations could now get more advanced.

One of the most important applications of mathematics in the Middle Ages was the study of time, and the development of tools to measure it.

Monasteries found several needs to accurately measure time, both in terms of the liturgical calendar and for daily task management. Advancements were made to mechanize clocks in churches and monasteries, including those constructed by Richard of Wallingford in St. Albans by 1336, and by Giovanni de Dondi in Padua from 1348 to 1364.

Later in the 16th and 17th centuries, further advancements were made in spring-based clocks and watches, and then by pendulum clocks, first thought up by Galileo. The increasing accuracy in measuring time is critical in our story, because without it, global navigation would not have been impossible. You see, you need a couple of clocks to measure longitude - one to tell you the time from where you set sail, and one to tell you the time where you are. And the eventual management of factories would have been untenable without clocks.

But Medieval Europeans didn’t stop mechanization with the clock.

In the 1430s, a German goldsmith started making lead molds of letters for a new device he was building. His name was Johannes Gutenberg, and within the next fifty years, more than a thousand of his printing presses could be found across Europe.

The printing press is frequently cited as the most transformative invention of history. Like most of the inventions I’m telling you about today, it actually originated in China. But for reasons I’ll get to another time, it didn’t really take off in China. It had its transformative impact in Europe. In the decades after Gutenberg, the prices of books and pamphlets fell dramatically. Literacy rates skyrocketed. For the first time, laypeople were reading the Bible in their own homes, without any priests around. And oh boy, is that ever going to shake things up.

And as more people learned how to read, many also learned for the first time that they were farsighted. Fortunately, there was something they could do about it.

Following the 1201 sack of Constantinople, a community of glassmakers from modern-day Turkey decided to relocate to the city of Venice. For the next 90 years, they made some of the best glass in Europe, and on occasion accidentally burned down their neighborhoods. After all, Venice was a city made of wood in those days, and glassmaking requires the use of hot furnaces. So the government of Venice decided to exile their glassmaking industry to the island of Murano.

Venice had inadvertently set up what economists call a “cluster” – an innovation hub. Over the decades, big advancements were made in glass. The biggest came when one Angelo Barovier decided to burn seaweed, rich in potassium oxide and manganese, into ash and then add it to molten glass. He called the result “cristallo” – it was clear glass, the first in history.

By this point, monks in northern Italy had already figured out how curved glass could help enlarge words on a page. They went ahead and invented eyeglasses. And now, with clear, transparent glass, these spectacles were better than ever.

The rise in literacy that accompanied the printing press meant a boom in the eyeglass industry. By the 1550s, lenscrafters were everywhere in Europe.

In the 1590s, one father-son lenscrafting duo in the Netherlands made a breakthrough, simply by lining one lens on top of another. Hans and Zacharias Janssen had just invented the microscope. Later on, Zacharias would also be among a group of Dutch lenscrafters to invent the telescope.

The printing press and lenses led to a dissemination of knowledge, including scientific thought. Soon, scientists were building on each other’s discoveries, and common folks were reading it, applying the ideas to practical inventions of their own.

Galileo wrote down a theory about how machines transmit force, and Robert Hooke used the idea for the Hooke’s Joint. He’d also earn a little international fame by publishing illustrations of the stuff he saw under a microscope, giving readers a glimpse of an invisible world and setting the stage for modern medicine. Telescopes would similarly set the stage for advanced navigation. William Lee’s readings led him to invent the stocking frame. And over the course of a century, several people looked at mining pumps and ancient steam turbines to gradually develop the steam engine.

Yes, the printing press really does get the ball rolling for the industrial revolution. But for it to come together, Europeans also needed more favorable access to foreign resources. And that’s where their centuries of political disorder and killing each other is really going to come in handy.

The need to protect their holdings in the constant warfare of the Middle Ages had already led Europe’s kings and nobles to get really good at structural engineering by building large castles, capable of protection from attacks.

That the protection castles provided wasn’t going to last.

In 1340, the Iberians made a major push against the Moors. At the Battle of Río Salado, the armies of the kings of Castile and Portugal had met those of sultan Abu al-Hasan 'Ali and Yusuf I of Granada. Observing the battle were two English onlookers, the Earls of Derby and Salisbury. Among the supplies sent up from Morocco to reinforce the Muslims’ position were cannons. The English earls had never seen anything like them. But they knew they wanted some. Six years later, the English army was using cannons against the French at the Battle of Crécy.

The cannons were powered by a mixture of chemicals we call gunpowder. It was invented in China in the 9th Century and was later used in their wars against the Mongols. By the time the Mongols conquered China, they were using cannons too.

It’s not clear how gunpowder got to Europe, but it probably traveled up the silk roads. Roger Bacon already knew about it by 1267, when he wrote his Opus Majus for the pope.

Unlike the Chinese, who usually had a politically stable empire, the Europeans were constantly at war with one another, and knew that gunpowder could give them an edge in battle. As a result, they spent the next 600 years developing and refining gunpowder-based weaponry.

It started, of course, with the cannon, which required a lot of cast-iron work to be done, as well as ore and coal mining. And then the development of firearms led to a need for engineering skill and mass production. And as you’re probably guessing, all of these things are going to be important in the coming industrial revolution.

But they were also important for the purposes of conquest. And wouldn’t you know it: Just as Europe is existing the Middle Ages, they found a whole new world to conquer. Next week, on the Industrial Revolutions.


If you haven’t already, please go ahead and hit “subscribe” on whatever platform you’re using so you hear new episodes as they come out. And if you’re listening to it on Apple Podcasts, and you like what you hear, please be sure to give it a 5-star rating and a quick review. Those really do help. The Industrial Revolutions has a newsletter! You can sign up for it at www.IndustrialRevolutionsPod.com. You can also follow along on social media: @IndRevPod. That’s @ I-N-D – R-E-V – P-O-D on Facebook, Twitter, and Instagram. Thank you.

Dave Broker