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READ: Era 3 Overview

Between about 6000 BCE and 600 CE, societies grew bigger and more complex. Families joined with each other to make villages, and villages grew into cities. As foragers became pastoralists and farmers, they also became village dwellers and city-builders. People living in these societies, either by choice or by force, then constructed government and systems of religion to help manage the problems, and the opportunities, of bigger populations and more complex life-styles.
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. According to the authors, what are two ways innovation happens?
  2. What is an empire, according to the article?
  3. What were some technologies, developed in this period, that helped long-distance travel and trade networks emerge?
  4. How were cities different from foraging societies in terms of social systems?
  5. Within these social systems, who did writing serve first, and how?

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. Given what you have learned so far, can you make a list of the topics and transformations you think you will learn about in this era?
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 3 Overview: Cities, States, and Empires

A drawn image of many people in a procession walking into a grand, blue-colored gate adorned with animal carvings.
By Trevor Getz and Bridgette Byrd O’Connor
Between about 6000 BCE and 600 CE, societies grew bigger and more complex. Families joined with each other to make villages, and villages grew into cities. As foragers became pastoralists and farmers, they also became village dwellers and city-builders. People living in these societies, either by choice or by force, then constructed government and systems of religion to help manage the problems, and the opportunities, of bigger populations and more complex life-styles.
When the last era ended, the world was a patchwork of human societies. Our ancestors had spread from Africa to most of the world's continents and large islands. Some of them were farming and herding animals, while others still largely foraged for wild plants and animals. Many people did both. We ended the era by comparing and contrasting Neolithic farming and pastoral communities in different parts of the world. These societies had made enormous innovations over thousands of years and each of these communities had created unique new cultures.
But change in human history isn't only driven by innovation within a society. In fact that's not even the principal driver of change. We also learn from each other's societies. New techniques, strategies, ideas, and tools are invented in one place, and then they're shared with other regions. People in nearby societies see what their neighbors are doing, and either adopt their ideas (essentially copying them) or adapt them (changing them to serve their own needs). Some of the most important inventions in human history—like iron and ramen—were only invented once or twice independently, and then people around the world learned to use and love them!

Growing communities

In this era, we ask how new complex political and economic systems developed, and how their emergence affected their communities and their relationships with other communities. And there were a lot more, and bigger, communities in this era! Between about 6000 BCE and 600 CE, societies, significant population growth, and increasing population density happened in many parts of the world. Families joined with each other to make villages, and villages grew into cities. This was especially true in the Neolithic communities discussed in the last era. You may have noticed that this unit overlaps with the last one by several thousand years. That's because the two key transformations of Era 2 and Era 3 overlapped. As foragers became pastoralists and farmers, they also became village dwellers and city-builders.
A modern-day photo showing the ruins of Teotihuacan, which is made up of several multi-level structures.
Ancient ruins of Teotihuacan, Mexico. By BrCG2007, public domain.
In many places, cities and villages also came together under one government as states. Sometimes these states were centered on a single city, with many villages connected to them. This was an early pattern in Mesopotamia, for example. Sometimes there were several cities and lots of villages linked together. This happened quite early in Egypt. Over time, some states grew very large, and became empires—several groups of different communities ruled by one government, often with some inequality between the communities.
In fact, inequality was something of a feature of these new cities and states. While we often talk of these developments as evidence of positive changes, they also brought new problems. For a poor person in a city, or a conquered person in a large state, life was often brutal, dirty, and filled with hard work. But for others, the city and the state brought excitement and opportunity.

Village, metropolitan, and long-distance networks

Whether good or bad, humans living in these societies had many new experiences. This was due largely to the growth of communities and expansion of networks. There were also many new humans to have these experiences.
Populations grew dramatically in Era 3. The rate of growth sped up over time. It took 1600 years—between 2600 and 1000 BCE—for the world's population to double. It grew from about 60,000,000 to about 120,000,000 people. But it took only 1,000 years—between 1000 BCE and 1 CE—for the population to double again, to 250,000,000 people. So populations, like the size of communities and the extent of networks, grew in this period.
The most important networks for everyday life remained quite localized. Villages connected to each other and to local, nomadic people through village networks. As cities emerged, a new type of network developed known as a metropolitan network. This network connected cities with the villages and rural areas around them, which they could to some degree control.
But during Era 3, long-distance networks also gradually developed. In Eurasia, the domestication of horses allowed for much speedier communication and allowed rulers to extend their influence and control over people hundreds of miles away from the capitals of their empires. Similarly, the domestication of the camel in western Asia and Africa meant that people and goods could now move across deserts at an accelerated rate. At sea, new and improving ship-building and navigation technologies helped states and empires spread across larger areas. In many regions, infrastructure projects such as the building of roads connected empires in a more efficient way.
As a result, more people travelled—although the number of people traveling compared to the overall population was still quite low. But for those that did travel, they learned each other's languages and read each other's ideas. Interlocking networks of roads, trails, and sea lanes connected almost all parts of Afro-Eurasia. Such networks also existed in the Americas, across extensive areas of Mesoamerica and the Andean mountain spine of South America.

Increased trade, new experiences

Of course, each of these innovations also helped to stimulate production and distribution. Networks that allowed for the sharing of ideas and growth of communities across oceans and along land routes also stimulated trade. The most extensive trade route of this era was the Silk Road, which connected the imperial centers of Rome and Han Dynasty China during the second and first centuries BCE.
Long-distance trade played a role in concentrating immense amounts of wealth in the hands of a minority of people. Hunter-gatherers had lived in relative equality. But life in agrarian cities and states generally was different. These societies tended to have more sharply defined social classes. The elite controlled much of the wealth and had many other privileges. However, some cities and societies seem to have relatively little hierarchy, while others had a great deal.
A painting shows a person in a horse-drawn carriage shooting a bow and arrow at many people.
Egyptian painting depicting the Hyksos invasion and the use of domesticated horses in battle. Public domain.
Rulers and wealthy merchants also drove the development of writing, probably the most important development during this era. The ability to read and write was rare and generally something only the wealthy had. Therefore, writing deepened the distance between the elite and commoners. The first written texts were generally not love poems or novels. Writing started as a way to record the trading of goods and surpluses of food. Writing let merchants record that they had traded three goats for five bushels of wheat. It let rulers write down instructions to the commanders and governors overseeing the furthest edges of their state.
Writing also helped to solidify and spread an important element of increasingly complex cultures of cities, states, and empires. These were large- scale belief systems of people from different cultures and with different languages. Most people of this era believed in more local religions with their own set of rituals and practices. These systems of belief were particular to their community. Their sacred places were within their local environment and they worshipped their own gods and goddesses.
Image of a piece of papyrus. Drawn symbols are separated by vertical lines.
Papyrus of Ani. Egyptian hieroglyphics, which originated from a logographic script. By Flembles, public domain.
Beginning in Era 3, however, religions emerged that were portable—they were not tied to one place—and congregational—meaning they brought groups of people together. Many of the world's major portable, congregational religions appeared during this time. Zoroastrianism, Judaism, Hinduism, Daoism, Buddhism, and Christianity all appeared, as networks of commerce and cultural exchange in Afro-Eurasia were appearing for the first time. With these new connections across local communities and different languages, humans began adopting shared belief systems. From that perspective, the growth of world religions seemed inevitable due to growing connectedness. These particular systems of belief were by no means the same—and by no means inevitable. The leaders of these world religions struggled with persistent questions about suffering and meaning. They looked at these issues through different lenses and came to different conclusions. But they formed both networks and communities of great significance in this era. They helped to shape and connect human experiences over vast regions and over thousands of years.


Despite the growth of portable religions, empires, and long-distance networks, most people in Era 3 still lived lives that were very local. They barely moved a few miles from where they were born, and their deepest connections were with people in their own local communities or their language networks. Similarly, not everybody lived in big states or cities. In fact, foragers still populated large regions of the world. Within cities, states, and empires, life experiences were also very diverse. The wealthy and powerful might profit greatly from the growth of agriculture and trade to enjoy very high standards of living. But one of the enduring truths about the human transition to cities is that life did not universally improve. In fact, for many people, living in early settlements meant shorter and less healthy lives than hunting and gathering. So rather than thinking of Era 3 as one step in a chain of progress, you might use the evidence in this unit to think about how new political and economic systems developed in this era, how it changed the way people lived, and what might be the lessons we can take away from these answers that might be meaningful today.
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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