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READ: Era 5 Overview — The First Global Age

This era asks the question “what does it mean to live in a truly global system?” The Columbian Exchange, the Great Dying, and the Atlantic Slave Trade dramatically reshaped the human story. And that story was also significantly changed by the growing global power of western Europe.
The article below uses “Three Close Reads”. If you want to learn more about this strategy, click here.

First read: preview and skimming for gist

Before you read the article, you should skim it first. The skim should be very quick and give you the gist (general idea) of what the article is about. You should be looking at the title, author, headings, pictures, and opening sentences of paragraphs for the gist.

Second read: key ideas and understanding content

Now that you’ve skimmed the article, you should preview the questions you will be answering. These questions will help you get a better understanding of the concepts and arguments that are presented in the article. Keep in mind that when you read the article, it is a good idea to write down any vocab you see in the article that is unfamiliar to you.
By the end of the second close read, you should be able to answer the following questions:
  1. Why does the author argue that viewing the world divided in two is an ‘oversimplification’?
  2. What did networks look like in Afro-Eurasia immediately prior to 1492, according to the article?
  3. What did networks look like in the Americas before 1492, according to the author?
  4. Why, nevertheless, was 1492 and the development of the Columbian Exchange significant?
  5. What claims is the author making about later European innovations?

Third read: evaluating and corroborating

Finally, here are some questions that will help you focus on why this article matters and how it connects to other content you’ve studied.
At the end of the third read, you should be able to respond to these questions:
  1. What do the histories of horses, tomatoes, cows, and potatoes demonstrate about the importance of the Columbian Exchange for local societies in different parts of the world?
  2. Based on what you’ve learned in this article, and any other knowledge you may have on the subject, what are some ways that your life today has been impacted by the Columbian Exchange?
Now that you know what to look for, it’s time to read! Remember to return to these questions once you’ve finished reading.

Era 5 Overview: The First Global Age

A very old, drawn map using colors of green and blue to represent water and land.
Trevor Getz and Bridgette Byrd O’Connor
This era asks the question “what does it mean to live in a truly global system?” The Columbian Exchange, the Great Dying, and the Atlantic Slave Trade dramatically reshaped the human story. And that story was also significantly changed by the growing global power of western Europe.
People sometimes assume that until 1492 the world was divided in two. After all, it wasn't until 1492 that "Christopher Columbus sailed the ocean blue". But viewing the world as divided in two is a bit of an oversimplification. For one thing, even though people may have lived separate lives on opposite ends of the world, they were—and we are—all descended from the same ancestors. The people who lived in the Americas were distant descendants of people who'd traveled from Asia into the Americas. In addition to common ancestry, Europeans had traveled via sea to the Americas centuries before. In order to believe a narrative of two separate worlds, we would also have to ignore the people of Australasia, who occupied, in many ways, yet another world!

Hemispheric systems before 1492

This era asks students to consider what it means to live in a truly global system. But while 1492 may have been an important year for the global system, we will begin our era before 1492. We'll first look at the extensive internal exchange systems in both the Americas and Afro-Eurasia. By the thirteenth century, the Afro-Eurasian system was enormously strong, with the Khan of the vast Mongol Empire playing a key role. Then a plague wiped out this system, briefly, but it re-emerged again in the mid-fourteenth century. This was a less centralized model. Circuits of traders moved around large regions. Each circuit overlapped, so that traders from China could sell goods to merchants from Southeast Asia, and a different set of Arab, South Asian, and East Africans could move those goods on to Cairo or Baghdad, from where they might be sold to Europeans. Ideas, beliefs, and knowledge, of course, also moved along these routes.
Map shows the goods traded between The Americas and Europe, Africa, and Asia. There are goods such as fruits and vegetables, grains, and livestock, but also diseases.
Crops, animals, and diseases transferred between regions during the Columbian Exchange. By BHP.
IIn the Americas, as well, large trading systems and networks of shared cultural values and ideas stretched over long distances. One of these connected many societies in Mesoamerica and north into the Desert Southwest of what is now the United States. Another stretched along the Andes mountains in South America. There is even evidence that these two distant networks and trade systems may have overlapped somewhat.
But it is true that in 1491 no living Europeans knew that there were humans in the Americas. No one in the Americas knew there were humans in Europe. Interesting fact: there were no tomatoes in Italian food or potatoes in Irish food at this time. That's because tomatoes and potatoes existed only in the Americas. Another interesting fact: there were no horses or cows in the Americas in 1491. At that time, cassava—today one of the leading crops in sub-Saharan Africa—was found only in the Americas. Meanwhile, Ecuador is one of the world's leading exporter of bananas. But in 1492, bananas were exclusively an Afro-Eurasian crop.

The Columbian Exchange

This all began to change after 1492—the beginning of what historian Alfred Crosby named the "Columbian Exchange." Once the two hemispheric systems were connected, it wasn't only crops and animals that were exchanged. People also moved as a result of this exchange—and not always willingly. Millions of Africans and Europeans ended up in the Americas, a large proportion of the Africans traded into slavery. And diseases moved as well. Afro-Eurasian diseases such as smallpox, malaria, and cholera were previously unknown in the Americas. But these diseases would kill millions in the century that followed. These exchanges dramatically reshaped not just human life, but all life on Earth. As Crosby pointed out, the transfer of plant and animal species may have "caused the extinction of more species in the last four hundred years than the usual processes of evolution might kill off in a million."
Drawing of several ships coming toward land. The drawing depicts Columbus and his men being greeted by Native people with gifts.
“Columbus landing on Hispaniola” by Theodor de Bry, 1594. Public domain.
These outcomes illustrate what it means to live in a global system on many levels. We'll look at the ecological (environmental) and demographic (population) consequences of interconnection. We'll focus especially on the "Great Dying" of millions of indigenous people in the Americas. This was due primarily to the introduction of infectious diseases from Afro-Eurasia—including typhoid, malaria, and smallpox. The scale of the "Great Dying" can be illustrated in the following comparison. When the Spanish conquistador Hernán Cortés first invaded present-day Mexico, the native population was between 25 and 30 million people. Fifty years later, it was three million. Almost all of this depopulation was caused by disease. We'll also look at what this disaster meant for Europeans, some of whom settled this land and traded in its resources. We'll study the impact on Africans who were enslaved and brought to the Americas to produce those resources – and those who fought against the system. At a smaller level, we'll see some of the experiences that happened as Africans, Europeans, and Americans encountered each other for the first time.
A drawn depiction of a battle between the Spanish and the Aztecs. A Spanish man has brutally slain an Aztec man.
Interactions between the Spanish under Cortes and the Aztecs from the History of Tlaxcala. Public domain.
We'll also see how the interconnectedness of humans led to the creation of the first global system of production and distribution. This was spurred by silver, which became the great facilitator of global trade. Silver, which was mined primarily by enslaved peoples in the Americas, became the most used global currency from the 1550s. The areas that benefited most from the mining of silver were Spain, western Europe, and China.
Of course, one massive element of this new system was the Atlantic slave trade. Growing production of sugar and cotton, crops that originated in Afro-Eurasia but grew well in the soil of the Americas, relied heavily on slave labor. The vast profits made by slave owners and traders helped finance scientific and technological developments. This included developments like modern banking and insurance systems that evolved in part to finance the slave trade.

Changes and continuities

Amid these profound changes, some significant ways of life remained unaffected. We tend to emphasize cities and empires in the study of history. But as late as 1800, only around two percent of humans lived in urban areas. Ninety-five percent remained farmers. The rest were foragers or pastoral nomads. Most Africans were not enslaved. Rather, they continued to live in relatively stable African states and communities. Similarly, most Europeans and Asians were not dramatically enriched by the wealth of the Americas.
Still, the human story was dramatically reshaped by the Columbian Exchange, the Great Dying, and the Atlantic Slave Trade. It was also significantly changed by the growing global power of western Europe. Around the world, the growth of mining and deforestation led to increased energy production. But they also altered the world's physical landscape. Asia, which had long been the center of ideas and economic growth, began to lose some of its influence. Large regions of Africa were devastated by the Atlantic slaving system. They lost both population and productivity as kidnapping, war, and chaos extended over previously stable regions and countries. European states gained colonies in the newly discovered Americas and reaped the economic benefits of taking natural resources from these areas.
As the era continued, more goods and ideas were exchanged and improved upon. New discoveries, philosophies, and movements emerged. As in previous eras, both local invention and the adoption of ideas from elsewhere played a big role in these innovations. Many of the new discoveries and technologies emerged from European states. But those European innovations came as the result of the collective learning and exchanges that had taken place in Afro-Eurasia for thousands of years. They were also fortunate to draw on the resources of the Americas, many of them produced by enslaved Africans. This ability to learn from, and expand on, ideas from around the world, was ultimately one answer as to what it meant to live in a truly global system!
In the eighteenth and nineteenth centuries, these developments would create the conditions for a series of changes so explosive that we call them "revolutions". But that is a story for another era.
Author bios
Trevor Getz is a professor of African and world history at San Francisco State University. He has been the author or editor of 11 books, including the award-winning graphic history Abina and the Important Men, and has coproduced several prize-winning documentaries. Trevor is also the author of A Primer for Teaching African History, which explores questions about how we should teach the history of Africa in high school and university classes.
Bridgette Byrd O’Connor holds a DPhil in history from the University of Oxford and has taught Big History, world history, and AP US government and politics for the past 10 years at the high school level. In addition, Bridgette has been a freelance writer and editor for the Big History Project and the Crash Course world history and US history curricula.

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