Classical Evolutionary Theory: Unilineal Cultural Progress Explained

For most of human history, people simply lived their cultures. It took the eighteenth and nineteenth centuries, and the shock of European contact with vastly different societies across the globe, for scholars to start asking why cultures looked so different from one another in the first place. Their answer became anthropology’s first big theory: classical evolutionism. It was ambitious, confident, and, as we’ll see, deeply flawed. But understanding it is essential, because almost every later anthropological theory defines itself in reaction to it.

The basic premise: one culture, many stages 🔗

Classical evolutionary theory argued that all human societies move along a single track of development, from simple to complex, from primitive to civilized. This is why it’s called unilineal evolution: uni meaning one, lineal meaning line. There was only one path, and every society on earth was somewhere along it.

This meant evolutionists thought about Culture as a single, universal thing, not as many separate cultures. Differences between societies weren’t seen as different ways of organizing life; they were seen as different stages of the same underlying journey. A hunting-gathering band and an industrial nation weren’t two distinct systems. They were the same system, just caught at different points in time. Unilineal cultural evolution held that all societies followed this fixed, universal sequence, with European societies typically placed at the very top of the ladder.

Because the sequence was assumed to be fixed, evolutionists believed they could work backward and forward along it. If you knew where a society sat today, you could predict roughly what came before it and what would come after. This is what made classical evolutionism a genuine meta-theory: not just an explanation of one custom or institution, but a master framework meant to organize the entire order of human development.

Eurocentric criteria for progress 🔗

Who got to decide what counted as “advanced”? Almost entirely nineteenth-century white male European and American scholars, and they judged progress by how closely a society resembled their own. The closer a group was to Victorian Europe in appearance, technology, and social organization, the “higher” it was ranked. The further away, the more “primitive” it was considered.

Australian Aboriginal societies became the textbook example of this bottom rung. Their physical distance from Europeans, combined with their use of stone tools, led scholars to treat them as living windows into humanity’s earliest stage rather than as a distinct, adapted way of life in their own right. This assumption shaped some of the most influential scholarship of the era. Émile Durkheim built his study of religion around Aboriginal totemism precisely because he considered it the most primitive and simplest religion known at the time, reasoning that studying its most basic form would reveal something essential about all religion. Sigmund Freud made a similar move in Totem and Taboo, treating Aboriginal totemic practice as a window into the psychological origins of human civilization itself.

Ranking societies by proximity, not by understanding 🔗

Notice what this method quietly does: it studies a living, complex society not to understand it on its own terms, but to use it as a stand-in for imagined ancestors. That’s the core Eurocentric move at the heart of classical evolutionism, and it’s a habit later anthropologists spent decades trying to undo.

Bachofen and the theory of mother right 🔗

Swiss jurist Johann Jakob Bachofen applied the same evolutionary logic to gender and family structure. In his 1861 work on Das Mutterrecht, or Mother Right, he argued that human societies had first been organized around matriarchy, or descent and authority through the mother’s line, before eventually giving way to patriarchy.

Crucially, Bachofen didn’t treat this shift as neutral. He framed matriarchy, or Mother Right, as tied to a cluster of what he considered lower, passive qualities: the moon, night, wetness, and death, tied to the material and biological fact of birth. Patriarchy, by contrast, was linked to reason, law, abstraction, and active civilizational achievement, in his eyes the natural fulfillment of human development. Since he believed rational thought was a distinctly male capacity, any society organized around women’s authority was, by definition, an earlier and lesser stage.

This wasn’t just an abstract theory about the ancient family. It fit neatly into the broader justification structure of the era: if patriarchy represented humanity’s civilizational peak, then Western patriarchal society could be framed as history’s endpoint, and European conquest and colonization of other regions could be recast as the arrival of true civilization rather than domination.

When the evolutionists couldn’t agree on the sequence 🔗

If unilineal evolution were a solid scientific theory, its supporters should have converged on the same stages. Instead, they argued constantly about which sequence came first, with almost no empirical evidence to settle the question.

The clearest example is the dispute between Sir Henry Maine and figures like Bachofen and John McLennan. Maine, a lawyer well versed in Eastern legal traditions, argued the opposite of Bachofen: that patriliny, descent and authority through the father’s line, was the earliest form of human social organization, and that matrilineal systems were later deviations. Maine’s patriarchal theory directly contradicted the matriarchy-first sequence proposed by Bachofen and McLennan, and the resulting debate ran for decades without resolution.

These weren’t minor disagreements about details. They exposed the theory’s central weakness: without solid archaeological or ethnographic evidence, evolutionists were essentially constructing historical sequences through speculation and then arguing over whose speculation was more plausible. A theory that promised to reveal the fixed order of human progress couldn’t even get its own experts to agree on what that order was.

Tylor’s evolution of religion 🔗

Edward B. Tylor, often called the father of cultural anthropology, defined culture broadly, as something every human group possessed, just in varying degrees of development. His most influential contribution was a theory of how religion itself had evolved.

Tylor proposed that the earliest form of religion was Animism: the belief in a soul, or a spiritual double, existing alongside the physical body. His reasoning was psychological rather than archaeological. He argued that early humans, confronted with the mystery of death and the strange experience of dreams, reasoned their way to the idea of a soul that could separate from the body, since dreams appeared to show the soul leaving during sleep, and death showed it departing for good. This wasn’t ignorance, in Tylor’s view. It was a rational attempt to explain lived experience, made by minds fundamentally similar to those of modern people.

From animism to monotheism 🔗

From this animistic root, Tylor and other evolutionists traced a progression of increasingly complex beliefs: a concept of the afterlife, veneration of ancestors, rituals and sacrifice, worship of natural forces (Naturism), clan-based totemic worship (Totemism), belief in many gods (Polytheism), and finally belief in a single supreme deity (Monotheism). Christianity was placed at the very top of this ladder, treated as the most evolved form of religious thought a society could reach. Seen today, this sequence says less about religion’s actual history and more about how confidently nineteenth-century European scholars placed their own beliefs at the summit of human achievement.

Morgan and the architecture of kinship 🔗

Lewis Henry Morgan, widely regarded as the father of kinship studies and a central figure of the American evolutionary school, took a very different research path from Tylor’s armchair theorizing. He conducted direct fieldwork with the Iroquois (Haudenosaunee) in New York, an unusually hands-on approach for his era, and it shaped his entire theoretical framework.

Morgan argued that societies evolved from organization based on kinship, which he called societas, to organization based on territory and property, which he called civitas. In his view, this was one of the fundamental transitions separating “ancient” from “modern” society. His fieldwork among the Iroquois also led him to distinguish between descriptive and classificatory kinship terminology systems, a distinction that remains part of the anthropological vocabulary for describing kin terms today, long after his broader evolutionary scheme fell out of favor.

The ethnical periods 🔗

Morgan’s most ambitious contribution was his sequence of Ethnical Periods, a detailed framework mapping how social institutions, subsistence methods, family forms, political organization, and law all developed together, stage by stage, from savagery through barbarism to civilization. Each period, in his scheme, had its own characteristic technology and corresponding social arrangements, forming an interlocking system rather than a loose collection of separate observations.

What classical evolutionism left behind 🔗

It’s tempting to dismiss classical evolutionary theory entirely, given how thoroughly its central claims have been discredited. Its sequences were speculative, its ranking system was Eurocentric, and it consistently mistook the standards of one culture for a universal yardstick.

Yet its legacy in anthropology is more complicated than a simple failure. Despite their biases, evolutionists helped establish the radical-for-its-time idea that all human beings share one common Culture and are equally capable of developing it, a stance that pushed back against contemporary theories of biological racial hierarchy, even as it replaced them with a hierarchy of its own. Their attempts to systematically define institutions, name customs, and identify recurring social patterns, however speculative, gave later anthropologists a vocabulary and a set of questions to refine, test, and eventually overturn. As later critics of social evolutionism note, the theory’s downfall came largely from the accumulation of detailed ethnographic evidence that simply didn’t fit its neat, singular sequence, evidence that a more careful, fieldwork-based anthropology, building on figures like Morgan, would go on to collect.

Every subsequent school of anthropological thought, from historical particularism to functionalism to structuralism, defined itself partly by rejecting some piece of the evolutionist program. In that sense, classical evolutionary theory isn’t just a historical curiosity. It’s the starting point the entire discipline has been arguing with ever since.

What do you think? Now that ethnographic evidence has thoroughly disproved the idea of a single universal sequence of cultural stages, why do you think popular ideas about “advanced” versus “backward” societies still persist in everyday language? And when you look at Bachofen’s or Tylor’s frameworks, can you spot places where your own assumptions about “progress” might be doing similar work?

References

1. https://www.britannica.com/topic/unilineal-cultural-evolution
2. https://www.ebsco.com/research-starters/history/elementary-forms-religious-life-emile-durkheim
3. https://www.britannica.com/biography/Johann-Jakob-Bachofen
4. https://anthropology.ua.edu/theory/social-evolutionism/
5. https://www.britannica.com/biography/Edward-Burnett-Tylor