We were all born equal, and our birthplace was Africa. Whoever we are, wherever we live, whatever language we speak, whatever our customs and beliefs, whatever the color of our skin, at some point in the last two million years our ancestors lived in Africa.

It took several emigrations to get us to the four corners of the earth. One exodus, beginning 1.8 million years ago, brought some of our distant ancestors out of Africa but no farther than the warmer parts of continental Eurasia. Joined by African game like the rhino, the hippo, and the elephant, they made it...

Rousseau felt that to understand the origins of inequality, one had to go back to a long-ago time when nature provided all human needs, and the only differences among individuals lay in their strength, agility, and intelligence. People had both “anarchic freedom” (no government or law) and “personal freedom” (no sovereign master or immediate superior). Individuals of that time, which Rousseau called the “State of Nature,” displayed self-respect but eschewed self-love.

Most anthropologists do not like the phrase “State of Nature.” They do not believe in a time when archaic modern humans had so little culture that their behavior was...

Among clanless foragers like the Basarwa and Hadza, homicide was an individual matter. The assassin might be killed by his own relatives or a member of the victim’s family. In other cases, the perpetrator might go into hiding, while his relatives placated the victim’s relatives with food and valuables.

An important change in social logic, however, took place with the formation of clans: a kind of “us versus them” worldview seems to have been created. If someone from Clan A murdered someone from Clan B, it was considered a crime against the victim’s entire clan. This required a group response....

Each hunting-and-gathering society discussed so far had its own distinctive character. All, however, featured a set of common principles, a few of which we list here.

1. Generosity is admirable; selfishness is reprehensible.

2. The social relationship created by a gift is more valuable than the gift itself.

3. All gifts should be reciprocated; however, a reasonable delay before reciprocating is acceptable.

4. Names are magic and should not be casually assigned.

5. Since all humans are reincarnated, ancestors’ names should be treated with particular respect.

6. Homicide is unacceptable. A killer’s relatives should either execute him or pay reparations...

Inequality, according to Rousseau, began when self-esteem gave way to self-love. Foragers knew that as long as they suppressed ambition and greed, they would be well thought of. They were obligated to share food and reciprocate all gifts, yet they were discouraged from shaming their partners with gifts too grand to match. Once larger units such as clans had arisen, however, a number of societies witnessed changes in social logic. Such larger units might collaborate to support members who, in Rousseau’s words, “desired to be esteemed by others.”

Let us consider only two behaviors, gift-giving and marriage. Among clanless societies,...

We can excuse Rousseau for not knowing that some foragers found ways to create hereditary inequality. After all, societies like the Tlingit and Nootka were largely unknown to Europeans in 1753. It is also the case that for most parts of the world, Rousseau was right: not until people had begun to raise crops or animals do we see signs of emerging inequality.

To be sure, even successful agriculture does not always lead to inequality. Many societies remained egalitarian even after thousands of years of farming. Others, as we see in this chapter, allowed modest amounts of achieved renown but...

Foragers often create ritual space by arranging their shelters in an oval. The enclosed area can then be used for feasting or dancing, sometimes around a communal hearth.

Farming villages, for their part, often formalize ritual space by creating a building to house it. In aboriginal North America that building could be a sweat house, a kiva, or a ceremonial lodge. We will see examples of those buildings in the chapters that follow. In other regions the ritual building might be a men’s house.

The ground plans of men’s houses vary considerably. Some are circular, and others are rectangular. Some...

At the start of the twentieth century, village societies with achievement-based leadership were among the most common in the world. They were remarkably stable societies, made up of descent groups that exchanged brides and gifts, honored their ancestors, considered everyone equal at birth, yet threw their support behind gifted kinsmen who sought to achieve renown.

Such societies were also widespread in prehistory; we probably all have ancestors who lived in one. Once you know what to look for, you can identify them in the archaeological records of the Near East, Egypt, Central and South America, North America, and Africa. Achievement-based...

The early village societies of Mexico, Peru, and the Near East went on to develop hereditary rank and never looked back.

Not every society with achievement-based leadership, however, underwent such a transformation. Many agricultural village societies resisted every attempt to increase inequality. They found a way to let talented people rise to positions of prominence while still preventing the establishment of a hereditary elite. The balance they struck between personal ambition and the public good allowed their way of life to endure for centuries.

Some of the best known of these societies were the Tewa, Hopi, Mandan, and Hidatsa of...

Leadership in New Guinea and the Solomon Islands and in the Southwestern pueblos and Plains villages of North America was traditionally based on achievement. Those societies had no hereditary aristocracy. Mandan leaders could sell their sacred bundles to their sons, but they could not present them with noble titles in the manner of Nootka chiefs.

The archaeological record tells us that at various times in the past, a number of achievement-based societies must have altered their social logic to allow for hereditary privilege. Unfortunately, archaeology shows us the results but not the logic itself; to reconstruct the latter, we must...

We have seen that agricultural villagers do not surrender their equality without a fight. No sooner does one social segment achieve elite status than its privilege is challenged, forcing it to resume its quest for supremacy. Cycling between ranked and unranked was probably common in the preindustrial world. Eventually, however, the leadership roles in some societies became hereditary in perpetuity.

One part of the world where hereditary rank flourished was the South Pacific. To be sure, most Polynesian islands were colonized by people from places that already featured some degree of inequality. On a number of archipelagoes, however, the level...

Some 3,500 years ago, achievement-based societies spread over the highlands of Mexico and Peru. Many of these societies built small ritual structures that resemble the familiar men’s house of the preindustrial world.

Parts of the Third World continued to build men’s houses well into the twentieth century—but not so in Mexico and Peru. In those two countries there came a time when achievement-based society gave way to hereditary rank. Once that happened, society’s leaders began to have temples built. Temples and small ritual houses coexisted for a while, but the latter eventually disappeared.

To be sure, the temples of...

We have learned a great deal from societies speaking Tibeto-Burman languages, but there is more to be learned. In this chapter we return to Assam to look at three more societies: the Dafla, the Miri, and the Apa Tani.

In the 1960s there were roughly 40,000 Dafla in the hills of Assam, all tracing descent from a legendary ancestor. The Dafla grew dry rice and millet by slash-and-burn farming and raised pigs, goats, oxen, and mithan cattle.

Like the Etoro of New Guinea, the Dafla lived in longhouses that accommodated up to 12 families. Also like the Etoro, they displayed...

Temples, as we have seen, went on to replace men’s houses in several parts of the New World. In the cases we have examined, the transition was accompanied by evidence for hereditary inequality. This fact does not surprise us because we have seen that as chiefly elites emerge, they begin to dedicate buildings to the highest celestial spirits in their cosmos.

Now we must search for a comparable transition in the Old World. We have chosen Mesopotamia because its societies were among the first to replace the small ritual house with the temple. Beginning 8,700 years ago with the Terrazzo...

From Memphis to New Orleans, the Mississippi takes a winding route past wetlands and antebellum mansions and the oxbows of its former course. With his windows shut and his air conditioner on, the traveler passes signs for barbecues and po’ boys, Delta blues, and the well-groomed battlefields of the War between the States. A few miles south of Natchez, Highway 61 crosses a tributary called St. Catherine Creek. If the traveler picks this moment to text message, he misses a chiefly center of historic importance.

The Fatherland site, as the former chiefly center is known today, was partly defended by...

In most of the world’s chiefly societies rank formed a continuum from the chief to the lowliest free citizen. Under the right conditions, however, rank societies sometimes made the transition to stratification. This amounted to drawing an invisible line across the continuum, thereby establishing a sharper break between the rulers and the ruled.

Social strata were usually kept separate by a behavior anthropologists call class endogamy. That simply meant that members of each stratum were only supposed to marry their peers. If a man of noble birth took a commoner wife, any children she bore him were less than noble....

We come now to a multigenerational process that changed Hawai’i forever. Beginning at least 800 or 700 years ago, certain Big Island chiefs began trying to expand their territories to include other islands. The earliest attempts rarely succeeded, but later chiefs kept trying.

Around A.D. 1270, for example, a Big Island chief named Kalanuihua is said to have conquered Maui and Moloka’i and invaded O’ahu. He overextended himself by attacking Kaua’i, where he was taken prisoner.

To be sure, before expanding to other parts of the archipelago it was necessary for a chief to solidify control of his home island....

We have just described the birth of four kingdoms. Each was created by a series of ambitious leaders, who kept trying until they had unified a group of formerly independent rank societies. The leaders involved had no model to follow and no template to show them what a monarchy should look like. All four cases, therefore, qualify as first-generation kingdoms for their regions.

Admittedly, the reason we know so much about the Hawai’ian, Zulu, Hunza, and Merina cases is because there is written documentation. All four cases took place late in world history, while Western observers were watching. Wouldn’t it...

The world’s longest river has two main branches. The White Nile begins at Lake Victoria in Uganda. The Blue Nile begins near Lake Tana in Ethiopia. Both branches are fed by the summer rain of the tropics. White and Blue join at Khartoum in the Sudan and then pick up more water from the River Atbara. It is the last water the Nile will receive on its journey to the Mediterranean.

The Nile is almost 3,900 miles long, surpassing both the Amazon and the Mississippi. So full is its Blue branch at flood stage that its water dams up that...

The first kingdom on the African continent was that of Egypt. More would follow. Some, like Aksum on the upper Nile, borrowed strategies from their Egyptian neighbors. Others, like the Zulu kingdom, were created by the iron-working, cattle-herding descendants of the Bantu migration. Still others arose among the matrilineal, horticultural societies of central and western Africa. Some African kingdoms, prevented by tsetse flies from relying on cattle, found that their wealth could be based on ivory, gold, or slaves.

Once the first kingdom has appeared in a region, it provides a model for later generations of kingdoms. Archaeologists can date...

Of all the world’s first-generation states, none were earlier than those of the Near East. They formed at a time when it was still not certain that Hierakonpolis would emerge triumphant in Upper Egypt. They formed at a time when permanent villages had yet to appear in Mexico and Peru.

Thirty years ago, Southern Mesopotamia was considered “the cradle of civilization.” Today we know that proto-states were also forming in Northern Mesopotamia and southwest Iran at about the same time (Figure 64). These three regions were all in contact with each other, providing us with another example of a chain...

They called themselves “the black-headed people,” a likely reference to raven hair. During the Early Dynastic period, 5,000 to 4,350 years ago, they dominated Southern Mesopotamia. For two centuries, 4,350 to 4,150 years ago, they lost their autonomy to people speaking a different language. During the Third Dynasty of Ur, 4,150 to 4,000 years ago, they returned to power, only to be ravaged by invaders and internal revolt.

We call the land of the black-headed people Sumer. While that land has seen extensive archaeological survey and excavation, much of what we know about the Sumerians is the product of epigraphy,...

An empire is a kind of macro-state and has its own social and political logic. In many parts of the world we can point to multiple generations of kingdoms and empires. This allows us to observe third- and fourth-generation states borrowing strategies from their predecessors.

Two New World societies can serve as examples. The Aztec belonged to the fifth generation of states in central Mexico. The Inca constituted the fourth-generation empire in the Andes. Both used the logic of their predecessors as templates.

The Basin of Mexico lies 7,200 feet above sea level and occupies 3,700 square miles. When the...

Our earliest ancestors were all born equal, but the Ice Age had barely thawed when some of them began surrendering bits of equality.

The rise of complex human societies, which began with hereditary rank and peaked with empires, has been compared to hypertrophic growth in biology. Social complexity, however, was not caused by genes. It grew out of perceived differences in life force, virtue, intellectual property, generosity, debt, and prowess in combat.

In biological evolution, population increase is considered a measure of success. One species grows at the expense of others. Either brand-new genes made it more successful, or a...