institutional drift

Institutional drift is the gradual, contingent divergence of societies’ political and economic institutions. Small differences in customs, property rights, authority, and conflict resolution can accumulate—or disappear and reappear—and later become decisive when a critical juncture disrupts the existing balance of power. The concept links long historical sequences to divergent outcomes while rejecting the idea that those outcomes were predetermined.

Definition and Mechanism

Societies do not begin with identical institutions. They develop distinct customs, systems of property rights, rules for dividing resources, and arrangements for recognizing authority or concentrating political power. Even relatively similar communities resolve conflicts over income, power, and institutions in different ways, shaped by particular historical circumstances, individual action, and chance. These differences are the starting material for institutional drift.

The book compares the process to genetic drift: just as separate populations can diverge gradually through random mutations, otherwise similar societies can move apart institutionally over time. Drift has no predetermined direction and need not be steadily cumulative. Differences may grow, recede, and emerge again; centuries later they may be perceptible and important, even if their beginnings were slight. The analogy explains gradual divergence, not a fixed path toward any particular institutional arrangement.

Institutional drift matters especially in combination with critical junctures: major events or convergences of circumstances that disturb a society’s political or economic balance. Existing institutions shape which responses are feasible and which groups can organize effectively. A disruption can therefore amplify modest institutional differences, directing societies toward contrasting outcomes. Those outcomes remain contingent on the forces that prevail, the coalitions formed, and the leaders able to shape events.

Critical Junctures and European Divergence

The Black Death shows how a shared shock could have different consequences in societies whose institutional arrangements had already begun to diverge. Before the plague struck in 1346, Western and Eastern Europe had relatively small differences in political and economic institutions. In the East, however, lords were somewhat better organized and held more consolidated land; towns were weaker, and peasants less organized. When the feudal order was shaken, Western workers gained freedom from feudal dues, fines, and regulations, while Eastern peasants became increasingly coerced as suppliers of agricultural goods for western markets. The same disruptive juncture opened a path away from feudal constraints in one region and intensified extraction in another, contributing to the Second Serfdom.

The consequences of this earlier divergence shaped later responses to the expansion of Atlantic trade after 1600. The English Crown could not monopolize overseas trade as thoroughly as the monarchies of France and Spain. English traders who profited from Atlantic commerce had relatively few ties to the Crown and pressed for limits on royal power; they played a critical role in the English Civil War and the Glorious Revolution. In France and Spain, the monarchy and its allies captured more of the gains. The opportunity of Atlantic trade was a critical juncture, but its effects depended on institutional differences that had developed earlier. In England it helped create pressure for greater pluralism; in France and Spain it strengthened the monarchs.

The account rejects a simple, cumulative story in which institutions steadily improve until prosperity follows. Venice, whose prosperity had rested on institutions with important inclusive elements, later closed its political and economic system to new entrants. Its existing elite restricted participation and prohibited economic institutions that had helped generate prosperity. That reversal demonstrates that institutional development can turn back: earlier movement toward inclusion does not guarantee that it will endure.

Contingency, Reversal, and Political Conflict

Institutional drift is not a claim that history moves inevitably toward larger differences or more inclusive arrangements. Small distinctions can be reversed and later reappear; the book points to Roman Britain as an example of this instability. Nor do earlier historical influences determine which society will eventually develop the most inclusive institutions. Rome shaped later European laws and institutions, and its collapse contributed to a decentralized political landscape and the development of feudalism. But inclusive institutions later took especially firm root in England, where Roman rule had been weakest and disappeared most decisively in the fifth century. Historical influence mattered without dictating the eventual result.

The book’s account of the Black Death also connects institutional change to longer processes set in motion by the fall of the Western Roman Empire. In Europe, the decline of slavery and the emergence of independent cities were prolonged, contingent developments. When the Black Death later weakened feudal society, stronger towns and a peasantry less bound to the land emerged from the disruption. These shifts were consequential because earlier institutional drift had helped create different starting conditions across Europe. The historical sequence is therefore neither a straight line nor a set of isolated shocks: inherited arrangements condition responses, and the consequences of those responses become part of the starting point for later change.

The framework also emphasizes political conflict over who gains, who loses, and who holds decision-making power. Extractive institutions may reinforce one another and persist through a vicious circle, while inclusive institutions can reinforce one another in a virtuous circle. Neither pattern is absolute. Major change occurs when existing arrangements meet a critical juncture, but a juncture does not mechanically determine the result. The same broad disruption can lead to different outcomes because prior institutional differences shape political feasibility, while coalitions and leaders affect which possible path is taken.

Cases Beyond Europe

The concept also helps explain why a formally widespread distribution of political voice need not produce inclusive institutions. Somali society had dispersed political authority, with adult men able to participate in informal councils, but it lacked a centralized state capable of reliably enforcing order or property rights. Clans and diya-paying groups developed rules for obligations, compensation, and collective redress; conflict over scarce water and grazing land repeatedly tested those arrangements. In the book’s account, the absence of central enforcement meant that dispersed authority did not, by itself, provide the conditions needed to adopt new technologies or build the organizations associated with industrialization. The case illustrates that institutional forms have consequences through their operation in a particular historical and political setting, not through labels alone.

The Tswana institutions described in the account offered a different configuration. The kgotla, a general assembly of adult men, provided a forum for debate over policy and disputes and could overrule a chief. Chieftaincy was not strictly hereditary in practice: political competition could displace an ineffective ruler and elevate a more capable candidate, a process expressed in the proverb “Kgosi ke kgosi ka morafe.” The Tswana chiefs’ authority and the participatory character of their institutions helped them act collectively at a later critical juncture, when they traveled to London and resisted Cecil Rhodes’s attempt to take their territory. Institutional inheritance did not make their success automatic, but it gave them means to respond.

The account argues that the chiefs helped preserve Tswana independence and limit British intervention, avoiding both intensified indirect rule and the more severe prospect of annexation by Rhodes. When Bechuanaland became Botswana in 1966, the country was exceptionally poor and surrounded by hostile white-ruled states. Its later growth was not the automatic payoff of an uninterrupted institutional ascent. Rather, the earlier episode illustrates how institutional drift and political organization could shape a response to colonialism, while the later transition depended on another critical juncture.

Significance

Institutional drift explains how small differences become historically consequential without treating them as destiny. The same societies may begin with broadly comparable arrangements yet diverge as their institutions shape responses to shocks, new opportunities, and conflicts over power. The Black Death and Atlantic trade reveal the mechanism at different scales: disruptive events interact with inherited differences, and their effects can amplify divergence across generations.

The idea also sets limits on explanations based solely on knowledge, geography, or cultural uniformity. Ghana’s economically irrational industrial projects, for example, are presented not simply as errors caused by ignorance: Kwame Nkrumah had access to advisers who understood their weaknesses, while the political incentives sustaining his regime shaped policy choices. The broader point is that institutional arrangements influence which policies leaders pursue and which groups can constrain them. Likewise, institutional change can reverse, and societies that escape extractive patterns do so through contingent political struggles rather than an inevitable historical progression. Institutional drift is thus the slow-making background to critical junctures, not a prophecy of what must follow.