Historical Evolution of Slums: From Ancient Times to Modern Cities

Slums are often treated as a modern problem – a consequence of today’s rapid urbanization, inequality, and urban poverty. But the reality is far older and more layered. Poor, overcrowded, and neglected urban settlements have existed for as long as cities themselves. Tracing the history of slums – from the apartment blocks of ancient Rome to the sprawling informal settlements of 21st-century Asia and Africa – reveals a consistent pattern: when cities grow faster than their capacity to house the poor, slums follow.

The roots of slums in ancient cities 🔗

Ancient Rome offers the earliest documented evidence of slum-like conditions in urban history. Insulae – tall, multi-storey apartment blocks built for profit by wealthy landlords – housed the majority of Rome’s population. Unlike the grand domus of the elite, these buildings offered no open courtyards or gardens and no private bathing spaces. Builders divided floor space into cramped rental units, and each level became more unsafe, dim, and unsanitary as one climbed higher.

Beyond the insulae were even more precarious structures known as cellae – informal spaces tucked under staircases, inside storage vaults, or behind taverns. These lacked proper roofs, solid walls, or fresh air. Residents cooked indoors on makeshift braziers, collected water in clay pots from street fountains, and emptied waste into gutters, where it mixed with runoff and animal dung, attracting flies, vermin, and frequent disease.

Rome was a densely populated city, approaching one million residents under Augustus, and ancient sources consistently describe a world where poverty reigned – streets filled with confusion, stench, lack of sanitation, crime, and violence as the corollary of overpopulation. While some of this imagery was literary exaggeration by aristocratic writers, the structural conditions of housing inequality were real and well-documented.

Medieval ghettos: segregation as a form of slum-making 🔗

In medieval Europe, the forces that created slum conditions shifted from overcrowding alone to deliberate social exclusion. In many instances, ghettos were places of terrible poverty, with small and crowded houses cramped along narrow streets, especially during periods of rapid population growth. The most historically significant example was the Jewish ghetto – a unique form of forced urban segregation that spread across European cities from the 13th century onward.

The word “ghetto” itself has a traceable origin. The term was first used in Venice in 1516, when authorities required Jews to move to the island of Carregio, across from an area where an old copper foundry was located. The ghetto was enclosed by a wall, its gates were locked at night, and residents had to observe a curfew. Because lateral expansion was impossible, buildings grew taller and more congested. Since expansion of the ghetto was as a rule impossible, houses tended to be of unusual height, with consequent congestion, fire hazards, and unsanitary conditions.

The Jewish ghettos of pre-emancipation Europe were not only physically degraded spaces – they were products of political and religious policy. In 1555, Pope Paul IV’s proclamation required the Jews of Rome to live in separate quarters, relocating them to a crowded and unsanitary area regularly flooded by the Tiber River. While the ghetto was a place of squalor, the rest of the city was being built up with magnificent churches. This deliberate contrast served ideological purposes, reinforcing social hierarchy through the built environment.

What made the medieval ghetto a distinct and important category in the history of slums was its combination of forced segregation, ethnic homogeneity, and multi-generational isolation. The Jewish ghetto was a unique type of medieval urban slum. Its uniqueness stems from an interesting and complex set of social, religious, political, and economic factors that created a unified, homogenous group which often lived for centuries, isolated from the rest of society in slum-like conditions.

Industrialization and the birth of the modern slum 🔗

The most decisive turning point in the history of slums came with the Industrial Revolution of the 18th and 19th centuries. The industrial revolution in England had by the beginning of the 19th century led to rapid urbanisation. Push factors from the rural areas – poverty, disease, changes in agriculture, and displacement of peasant farmers – and pull factors from the cities – industrialisation and the growth of Empire – led to huge urban growth in places like Liverpool, Manchester, York, and Birmingham.

The scale of population movement was staggering. In England and Wales, the proportion of the population living in cities jumped from 17% in 1801 to 72% in 1891. Manchester experienced a six-times increase in its population between 1771 and 1831, growing from a town of 10,000 in 1717 to 2.3 million by 1911. Cities simply could not build fast enough to house this influx.

Friedrich Engels and the documentation of industrial slums 🔗

The most influential account of what industrial urbanization did to the urban poor came from Friedrich Engels. In The Condition of the Working Class in England in 1844, Engels described the backstreets of Manchester and other mill towns, where people lived in shanties and shacks, some not enclosed, some with dirt floors. His observations were not merely political commentary – they were a sociological record of what rapid, unregulated industrial growth produced.

There were no building regulations in place and many houses were overcrowded. It was not unheard of to find a whole family living in one room or an entire street sharing one set of outdoor toilets. Houses were put up quickly and cheaply in order to provide for the huge numbers of workers, and were often poorly built and unsafe.

The low wages of industrial workers permitted no decent quarters. The rapidly increasing industry multiplied the number of urban masses, and the tenements of the working class were made of poor material – rooms were small and low, baths were omitted, and toilet facilities and water outlets had to be shared by several people. Disease spread rapidly in these conditions: an outbreak of cholera in Manchester in 1832 killed 496 people, with another in 1849 killing a further 545.

The origin of British slums during the 19th century, as historian Lewis Mumford explained, was directly tied to the factory system and the industrial modern city. The modern slum, in this sense, was not just a housing problem – it was the spatial expression of industrial capitalism’s class divisions.

The U.S. experience: urbanization at accelerated speed 🔗

In the United States, the process of urbanization was quicker than in Europe, and low-paid workers immigrated in masses. Big slums became essential phenomena of a few large cities. The invention of the automobile and the subsequent exodus from more centrally located residences added to the deterioration of once satisfactory areas. Two World Wars, during which building activities were sharply curtailed, added further to the slum problem.

Colonialism also played a role in the formation of slums beyond Europe and America. Dharavi slum in Mumbai – now one of the largest slums in India – began as a village called Koliwadas. In 1887, the British colonial government expelled tanneries and poor natives from the peninsular part of the city to what was then the northern fringe, a settlement now called Dharavi. This settlement attracted no colonial supervision or investment in terms of road infrastructure, sanitation, public services, or housing.

The 20th century: slums go global 🔗

By the 20th century, slum formation was no longer confined to industrializing Europe or North America. As urbanization spread to the Global South, so did the dynamics of slum creation. The pattern was consistent: rural-to-urban migration driven by economic necessity, cities unable to provide adequate housing, and the urban poor constructing informal settlements on available land.

Since 2007, more than half the world’s population has been living in cities, and that share is projected to rise to 60% by 2030. Rapid urbanization has resulted in a growing number of slum dwellers, inadequate and overburdened infrastructure and services, worsening air pollution, and unplanned urban sprawl.

The numbers today are staggering. The absolute number of people living in slums or informal settlements has grown to over 1 billion, with 80% attributed to three regions: Eastern and South-Eastern Asia (370 million), sub-Saharan Africa (238 million), and Central and Southern Asia (227 million). According to the Cities Alliance, UN-Habitat anticipates that 90% of the 21st century’s urbanization will take place in developing nations, and by 2050, two-thirds of the global population – around seven billion people – will live in urban areas.

The world’s largest slums today – Orangi Town in Karachi (2.4 million), Neza in Mexico City (1.2 million), and Dharavi in Mumbai (1 million) – are direct products of this decades-long process. They are, in scale and character, far removed from the insulae of Rome, but they share the same structural foundation: economic inequality, rapid population movement, and inadequate housing supply.

Continuities across history: what slums have always reflected 🔗

What the historical record makes clear is that slums have never been accidental. They are the predictable outcome of specific socioeconomic conditions – the concentration of the poor in urban spaces when economic systems prioritize growth over equitable housing. During the process of urbanization, some agricultural land is used for additional urban activities, land values rise, and the gap between people’s low income and high land prices forces some to construct cheap informal settlements.

From the insulae of ancient Rome to the ghettos of medieval Venice, from the factory slums of Manchester to the informal settlements of Nairobi and Mumbai, the thread connecting these places is consistent: when economic and political systems fail to distribute urban resources equitably, slums emerge as the physical result. As A.R. Desai and S. Devdas Pillai noted in their study of slums and urbanization, constitutional rights to property, movement, and life coexist – uncomfortably – with no guaranteed right to adequate housing, work, or livelihood for the urban poor.

Understanding this history is not simply an academic exercise. It is essential context for evaluating why slums persist despite decades of urban policy, and what it would genuinely take to address the conditions that produce them.

What do you think? Given that slums have existed across every era of urbanization – ancient, medieval, and industrial – do you think their persistence today reflects a failure of policy, or something more fundamental about how cities and economies are organized? And in comparing the forced segregation of medieval ghettos with today’s informal settlements, how much has really changed in the relationship between poverty and urban space?

References

1. https://www.historyskills.com/classroom/ancient-history/roman-houses/
2. https://www.myjewishlearning.com/article/jewish-ghettos-of-europe/
3. https://www.sociologygroup.com/slums/
4. https://www.citiesalliance.org/newsroom/news/results/global-effort-improve-worlds-slums
5. https://www.egyankosh.ac.in/bitstream/123456789/27707/1/Unit-23.pdf