Civilization: How Did Humans Start Living in Cities?

Ask when civilisation began and the answer arrives as a list rather than a date: farming, then cities, then writing, then law. Dated evidence turns the list into a stop-start. Fossils assigned to our species are about 300,000 years old. Domesticated plants and animals appear in southwest Asia about 10,000 to 11,000 years ago. In southern Mesopotamia, Uruk reaches 250 hectares around 3100 BCE, ten times any of its contemporaries. And the species only becomes majority-urban in the last two centuries.

This pillar is the hub for the Civilization cluster, and it makes one argument across the cluster's questions. The delay is not about intelligence. It is about coordination technologies that are boring, cumulative and expensive — counting, standardising, printing, piping — and about the bill each one leaves behind. Every technology here solved a problem between strangers by creating a dependence that could not be undone.

Three dates that do not line up

The oldest fossils assigned to Homo sapiens come from Jebel Irhoud in Morocco, dated to 315,000 years give or take 34,000 (Richter et al. 2017), with modern faces on archaic braincases (Hublin et al. 2017). The anatomy was in place long before the settlements were.

The first large farming town we can examine house by house is Çatalhöyük on the Konya plain, occupied from about 7100 to 5950 BCE. It covered 13.5 hectares, held an estimated 3,500 to 8,000 people, and was built as mudbrick houses packed against each other with few or no streets; people moved across the roofs and went home down a ladder through the ceiling (Çatalhöyük Research Project). A town of thousands, with no writing and no streets.

Uruk, in southern Mesopotamia, is the other kind of settlement: about 250 hectares by 3100 BCE, ten times the size of any neighbour, with a later wall enclosing 400 hectares (Ur 2012). Between Çatalhöyük and Uruk lies the whole distance between a place where many people live and a place where many strangers must be administered.

Table 1 gives the anchors used here.

Marker	Earliest securely dated	What the evidence is	Still disputed
Fossils assigned to Homo sapiens	315 ± 34 ka	Dated fossils and sediments at Jebel Irhoud	Where in Africa the species began
Domesticated plants and animals	10,000-11,000 years ago	Archaeobotany, faunal assemblages, survey	How intentional the first cultivation was
Town of several thousand people	7100-5950 BCE	Excavated houses and radiocarbon at Çatalhöyük	Whether to call it a town or a village
City of hundreds of hectares	250 ha by 3100 BCE	Survey and excavation at Uruk	Which site counts as the first city
Writing	3350-3100 BCE	Tokens, bullae and impressed tablets	How directly tokens became signs
Empire-wide standard weights	221 BCE	Inscribed Qin weights found across China	How far practice matched the edict
Movable-type printing in Europe	1450s	Surviving incunabula and city archives	Size of the economic effect
Majority-urban world population	2018 (55 per cent)	UN DESA figures in IPCC AR6	Where the threshold is drawn

Farming paid in calories and charged in health

Agriculture is a precondition of cities, not a cause of them, and the bill arrived early. The human remains from Çatalhöyük give an unusually continuous record across nearly twelve centuries, and the bioarchaeological reading is not flattering. Dependence on domesticated plant carbohydrates brings more dental decay and more periods of poor nutrition recorded in tooth growth; density, fuelled by elevated fertility, raises exposure to infectious disease; herding caprine animals and fetching resources shows up as heavier workload and greater mobility, not less. The authors also record interpersonal violence (Larsen et al. 2019).

That does not make farming a mistake. It makes it a trade: more people fed per hectare, at the cost of worse individual health and a narrower diet. The sequence matters more than the verdict. Density produced its costs before any writing existed to record them, which means the first cities were not solving a health problem. They were scaling one up.

The first city was a warehouse with a wall

Uruk's scale is what needs explaining. In the fourth millennium BCE towns across the southern alluvium were reaching 40 to 50 hectares; Uruk reached 250, roughly ten times any contemporary, and most of the 400 hectares inside its later wall was settled (Ur 2012). Scale at that level is not a large village. It implies a population that cannot be fed by the people in it.

The title of first city is contested, and the contest is instructive. Urban-scale settlement also appears in northern Mesopotamia at Tell Brak and Hamoukar by the early fourth millennium BCE, and the relationship between the two developments is not understood (McMahon 2020; Ur 2012). What makes Uruk the standard example is size plus apparatus: pictographic writing and cylinder seals tied to leadership and administration (McMahon 2020). A city, in the sense used here, is a concentration of people plus a technology for recording who owes what to whom.

That definition handles the awkward cases. Çatalhöyük was big and left no administration we can detect, and archaeologists argue over whether to call it a town at all. Uruk was big and left receipts.

Writing began as a receipt

The best-documented origin of a writing system is Mesopotamian, and it starts with small clay shapes. From about 7500 to 3350 BCE, farmers in the Near East used geometrically shaped tokens to count goods: a cone stood for a small measure of barley, a sphere for a larger one, a disc for a sheep, and quantity was expressed by one token per unit. Cities still used tokens to control the levy of dues: when people could not pay, the tokens standing for the amount owed went into a round clay envelope, and so that it could be checked without breaking, the tokens were pressed into its surface before sealing. Once that worked the tokens were redundant and the impressions became the record. The first impressed texts, from about 3350 to 3100 BCE, kept the old function: quantities of barley and animals delivered to temple granaries and sheepfolds (Schmandt-Besserat).

Two conclusions follow, and they differ in strength. The strong one is about Mesopotamia: its earliest readable writing is accounting, and narrative, law and literature are later users of a system built to track goods. The weak one, which the evidence does not support, is that every script everywhere began in a warehouse. Other writing systems need their own histories.

The consequence for cities is why Uruk remains the standard example: its pictographic writing and cylinder seals appear alongside monumental building, tied to leadership and administration (McMahon 2020). Whatever else a city of tens of thousands needed, it needed a record that outlives the person who made it, and writing is the first technology that does that at scale. The receipt is not a by-product of civilisation. It is the part that made the rest administrable.

Standards: the technology of agreement

Standardisation is invisible until it fails, which is why it is underrated as an invention. In 221 BCE, having unified the warring states, the first Qin emperor issued an edict on weights and measures. The edict runs to forty characters, was cast or inlaid onto bronze and iron weights distributed to commanderies and counties, and the state ran an annual inspection of the instruments. Surviving weights bearing the inscription have been found across a wide area, which is the physical evidence that the order was carried out rather than merely proclaimed (Henan Museum).

Modern standards keep the function and change the mechanism. The metre began as a physical artefact and is now defined by fixing the speed of light in vacuum at 299,792,458 metres per second, so any laboratory able to measure light and caesium can realise the unit without consulting an object in Paris (BIPM). The older kind of standard could drift or be copied badly. The newer kind is a constant.

Both kinds share the part that matters in a city: enforcement. A standard is a promise that a stranger's measure means the same as yours, and the promise holds only while somebody inspects, prosecutes or refuses the goods. Qin weights were an instrument of empire before they were a convenience. Every market since has rested on the same bargain, and the bargain is political.

Printing: measurable, but not magic

Printing is the case where an information technology's effect can be measured, and the measurement is narrower than the legend. Using city-level data for Europe, Dittmar compared towns with a press established before 1500 against towns without one. Over the sixteenth century the adopters grew about 60 per cent faster, with estimates running from 20 to 78 percentage points of extra growth, which would account for 18 to 68 per cent of European city growth in the period. Adopters showed no growth advantage before adoption, and the analysis instruments adoption with distance from Mainz, the birthplace of the technology (Dittmar 2011).

Book production is a longer and smoother curve than the invention story implies. Estimates across thirteen centuries of Western European manuscripts and printed books give an average annual growth rate around one per cent, with the rise after the mid-fifteenth century plausibly driven by lower prices and higher literacy rather than by the press alone (Buringh & van Zanden 2009).

So the summary is double-edged. Printing is the clearest case here of a technology with a measurable economic effect on cities — and the effect is on the growth of particular cities, not on productivity in general, where economists had struggled to find anything comparable. A technology can transform one variable and leave another untouched.

Pipes, pumps and the urban penalty

Rome is the ancient case of infrastructure outrunning knowledge. Over a little more than five centuries eleven aqueducts were built to supply the city with water. Frontinus, appointed water commissioner in 97 CE, calculated its total discharge at 14,018 quinaria; at one modern conversion of 40 cubic metres per quinaria per day that implies about 560,000 cubic metres delivered daily, while published estimates run from 520,000 to 635,000 and, at the outer end, as high as 1,000,000 — a spread wide enough to warn against ancient capacity figures (Deming 2020).

Water arrived. Health did not follow. Nineteenth-century cities still killed their inhabitants faster than the countryside did, and the size of the penalty is measurable: in Scotland in the early 1860s, life expectancy at birth in the principal and large towns was about 35.5 years for females and 32.6 for males, against 43.1 and 40.5 for the whole population. Torres and colleagues separate an urban penalty, the higher mortality of city dwellers, from an urbanization penalty, the effect on national survival of moving people into cities, and find both operating between 1861 and 1910 (Torres et al. 2019).

London's 1854 outbreak joins the two halves of the problem. Snow mapped cholera deaths in Soho against the pumps, found nearly all of them close to the Broad Street pump, and reported that 61 of the deaths he investigated involved people who habitually drank that water; the parish removed the handle on 8 September. He also recorded that attacks had already fallen before the handle came off, so the removal is a good story rather than a clean experiment (Snow 1855).

What moved the numbers was not the theory but the sanitation. Torres and colleagues report Woods's reading that the measures of the sanitary revolution in the largest cities were what prevented the urban-rural gap from widening further, and they date the convergence itself to the late nineteenth and early twentieth centuries (Torres et al. 2019). That is why the urban penalty belongs in this pillar. Infrastructure is the technology that turns density from a death sentence into a survivable default, and it arrived about five thousand years after the cities did.

Every fix moved the problem

Civilisation does not end the relationship between people and environment; it relocates it, measurably. Lead emitted by European lead-silver mining and smelting is preserved in Greenland ice, and a subannually dated record from 1100 BCE to 800 CE tracks Mediterranean history: emissions rose with Phoenician expansion, accelerated with Carthaginian and Roman mining in Iberia, fluctuated with wars, peaked under the Roman Empire, fell sharply with the Antonine plague, and reached their lowest point during the crisis of the third century (McConnell et al. 2018). Rome's economy is legible as pollution on another continent.

Dense settlement also created a new biological niche. Measles needs a continuous supply of susceptible people, and in nineteen island communities no population below 500,000 maintained transmission; the critical community size sits between roughly 200,000 and 500,000, and the author concluded that measles virus must have evolved after early civilisations appeared (Black 1966). Crowd disease is a product of cities, not a background condition of human life.

The pattern repeats at global scale: about 55 per cent of the world's population lived in urban areas in 2018, and urban settlements generate about 70 per cent of global carbon dioxide-equivalent emissions (IPCC 2022). The fuel base behind that is fossil fuel: burning it for buildings, transport and industry is a major source of urban emissions, and lock-in to it is named as an obstacle urban mitigation must overcome (IPCC 2022). Table 2 sets the technologies beside the problems they solved, the bills they created and the strength of the evidence.

Technology	Problem it solved	Cost or new dependency	Evidence strength
Farming	More calories per hectare, stored surplus	Poorer health, narrower diet, more disease exposure	Strong at Çatalhöyük; weaker for timing elsewhere
Accounting and writing	Obligations between people who do not know each other	Records become power; administration becomes necessary	Strong for Mesopotamia; not a universal origin story
Standard weights and measures	Trade, taxation, construction between strangers	Requires an authority that can inspect and enforce	Strong on artefacts; weaker on everyday compliance
Movable-type printing	Copying text cheaply and identically	Needs paper, literacy and markets to pay off	Strong local growth effect; no aggregate productivity effect
Aqueducts and sewers	Water supply and waste removal at city scale	Capital cost, maintenance, upstream capture	Strong on engineering; contested on delivered volumes
Fossil-fuel energy	Power at a scale muscles and water could not supply	Emissions, plus lock-in to fossil fuel that is slow to overcome (IPCC 2022)	Strong on aggregate shares; attribution varies with accounting method

Common misunderstandings

Civilisation is a single ladder of progress. Farming, city, writing, state is one region's route, not a law. Çatalhöyük was a settlement of thousands with no writing and no streets; Uruk had writing and administration; northern Mesopotamia had urban-scale sites from the early fourth millennium, with Tell Brak described as an earlier urban centre whose relationship to Uruk is unresolved (Ur 2012; McMahon 2020).

Writing was invented to record stories and laws. In Mesopotamia the earliest readable texts are deliveries of barley and animals to temple stores (Schmandt-Besserat). Literature and law come later, on top of a system designed for goods. That is a claim about one region, not about every script.

Cities made people healthier and richer. Not for most of their history. Early farmers at Çatalhöyük show more disease exposure and heavier workloads than the foragers they replaced (Larsen et al. 2019), and nineteenth-century cities had life expectancies about a decade below the surrounding countryside (Torres et al. 2019). The gap closed only in the late nineteenth and early twentieth centuries, with sewers and clean water.

One invention explains the modern world. Printing is the strongest candidate, and its measured effect is a 60 per cent growth advantage for adopting cities over one century, not a general productivity revolution (Dittmar 2011). The same restraint applies to writing and standards: each is necessary somewhere in the story, and none is sufficient.

Standards are technical, not political. A standard is only as good as its enforcement. Qin weights carried an imperial edict and were inspected annually (Henan Museum); the modern metre is guaranteed by a treaty organisation rather than by an object (BIPM). The definition is technical. The agreement to be measured by it is political.

Frequently asked questions

Why did civilisation take so long to appear?

Because the bottleneck was coordination technology, not intelligence. Fossils assigned to our species are about 300,000 years old (Richter et al. 2017), domesticated plants and animals arrive about 10,000 to 11,000 years ago (Larsen et al. 2019), and the first 250-hectare city appears around 3100 BCE (Ur 2012). Dense living only paid once counting and recording existed, and it stayed lethal until water and sewerage arrived.

Was writing invented for literature?

In Mesopotamia the earliest writing comes out of accounting. Clay tokens used from about 7500 BCE counted quantities of barley and animals, and when they were impressed on tablets between about 3350 and 3100 BCE they recorded the same deliveries to the same granaries (Schmandt-Besserat). Narrative and law arrive later.

Were cities less healthy than the countryside?

Yes, for most of urban history. In Scotland in the early 1860s, urban life expectancy at birth was about 35.5 years for females and 32.6 for males, against 43.1 and 40.5 for the whole population (Torres et al. 2019). The gap narrowed as water supply and sewerage caught up, and urban survival then overtook rural.

Was Uruk the first city?

It is the largest and best documented city of the fourth millennium, reaching about 250 hectares by 3100 BCE, roughly ten times its contemporaries (Ur 2012). Urban-scale settlement also appears by the early fourth millennium at Tell Brak and Hamoukar in northern Mesopotamia, and how the two developments relate is not known (McMahon 2020).

Sources

1. Richter, D., et al. (2017). The age of the hominin fossils from Jebel Irhoud, Morocco, and the origins of the Middle Stone Age. Nature 546, 293-296. https://doi.org/10.1038/nature22335
2. Hublin, J.-J., et al. (2017). New fossils from Jebel Irhoud, Morocco and the pan-African origin of Homo sapiens. Nature 546, 289-292. https://doi.org/10.1038/nature22336
3. Larsen, C. S., et al. (2019). Bioarchaeology of Neolithic Çatalhöyük reveals fundamental transitions in health, mobility, and lifestyle in early farmers. PNAS 116(26), 12615-12623. https://doi.org/10.1073/pnas.1904345116
4. Çatalhöyük Research Project. Çatalhöyük Site Guidebook, English edition. https://www.catalhoyuk.com/sites/default/files/Catalhoyuk-Guidebook-ENGLISH.pdf
5. Ur, J. A. (2012). Southern Mesopotamia. In D. T. Potts (ed.), A Companion to the Archaeology of the Ancient Near East, 533-555. Wiley-Blackwell. https://people.bu.edu/chamley/HSFref/Ur2012CompanionArchANE.pdf
6. McMahon, A. (2020). Early Urbanism in Northern Mesopotamia. Journal of Archaeological Research 28, 289-337. https://doi.org/10.1007/s10814-019-09136-7
7. Schmandt-Besserat, D. From Accounting to Writing. The University of Texas at Austin. https://sites.utexas.edu/dsb/tokens/from-accounting-to-writing/
8. Henan Museum. Qin Dynasty Weight with Qin Shihuang's 26th Year's Edict. https://www.chnmus.net/sitesources/hnbwy/page_pc/WeeklySelection/QinDynastyWeightwithQinShihuangs26thYearsEdict/list1.html
9. BIPM. SI base unit: metre (m). https://www.bipm.org/en/si-base-units/metre
10. Dittmar, J. E. (2011). Information Technology and Economic Change: The Impact of the Printing Press. Quarterly Journal of Economics 126(3), 1133-1172. https://doi.org/10.1093/qje/qjr035
11. Buringh, E., & van Zanden, J. L. (2009). Charting the Rise of the West: Manuscripts and Printed Books in Europe, a Long-Term Perspective from the Sixth through Eighteenth Centuries. Journal of Economic History 69(2), 409-445. https://doi.org/10.1017/S0022050709000837
12. Deming, D. (2020). The Aqueducts and Water Supply of Ancient Rome. Ground Water 58, 152. https://pmc.ncbi.nlm.nih.gov/articles/PMC7004096/
13. Snow, J. (1855). On the Mode of Communication of Cholera, 2nd edition. London: John Churchill. https://archive.org/details/b28985266
14. Torres, C., Canudas-Romo, V., & Oeppen, J. (2019). The contribution of urbanization to changes in life expectancy in Scotland, 1861-1910. Population Studies 73(3), 387-404. https://doi.org/10.1080/00324728.2018.1549746
15. Black, F. L. (1966). Measles endemicity in insular populations: critical community size and its evolutionary implication. Journal of Theoretical Biology 11(2), 207-211. https://doi.org/10.1016/0022-5193(66)90161-5
16. McConnell, J. R., et al. (2018). Lead pollution recorded in Greenland ice indicates European emissions tracked plagues, wars, and imperial expansion during antiquity. PNAS 115(22), 5726-5731. https://doi.org/10.1073/pnas.1721818115
17. IPCC (2022). Climate Change 2022: Mitigation of Climate Change. Contribution of Working Group III, Chapter 8: Urban systems and other settlements. https://www.ipcc.ch/report/ar6/wg3/chapter/chapter-8/

Explore this topic

This pillar is the hub for the Civilization cluster. Three cluster articles are already published:

• The Story of Titanium
• Why Did the Library of Alexandria Burn?
• Why Does New York Look Like New York?

One more is written but unpublished, listed by title only:

• planned: How Did Japanese Artists Print Fish Without a Camera?

Two questions in this cluster have no article yet:

• Why Did Humans Invent Writing? The Receipt That Started History
• Why Did Civilization Wait 290,000 Years? It Wasn't Brains

Everything with this pillar's label will collect at Civilization as the cluster publishes.