Under what conditions are user-generated digital content platforms responsive to pressures from users, businesses, and states? I propose that digital platforms show different levels of responsiveness to users, businesses, and states over time. Early in a platform’s life, the platform is highly sensitive to the demands of users, who have an opportunity to directly shape the institutional characteristics of the platform through the threat of user revolt. The unique power of its users stems from the network logic that underpins the value of the platform. As a platform grows and the size and centrality of its network increase, it becomes more sensitive to pressures by businesses (through boycotts) and the state (through regulation). At the same time, the power of users lessens as collective action problems become more severe and exit threats become less credible. The threat of user revolts has a temporal significance: Unless users alter the institutional architecture of the platform and lock in pro-user institutional characteristics early, the threat of user revolts becomes less consequential as the platform grows. Comparative case studies of Facebook, Wikipedia, Digg, and Reddit provide support for the theory.

Scholars usually portray institutions as stable, inviting a status quo bias in their theories. Change, when it is theorized, is frequently attributed to exogenous factors. This paper, by contrast, proposes that institutional change can occur endogenously through population loss, as institutional losers become demotivated and leave, whereas institutional winners remain. This paper provides a detailed demonstration of how this form of endogenous change occurred on the English Wikipedia. A qualitative content analysis shows that Wikipedia transformed from a dubious source of information in its early years to an increasingly reliable one over time. Process tracing shows that early outcomes of disputes over rule interpretations in different corners of the encyclopedia demobilized certain types of editors (while mobilizing others) and strengthened certain understandings of Wikipedia’s ambiguous rules (while weakening others). Over time, Wikipedians who supported fringe content departed or were ousted. Thus, population loss led to highly consequential institutional change.

Prominent theories of state formation hold that states formed because of warfare and competition on the one hand, or the diffusion of organizational templates and practices through learning and emulation on the other. We propose that the two strands of theory can be linked to more accurately account for mechanisms of state formation. War, we argue, is an important source of social diffusion. War establishes contacts between political elites across borders, generates migratory flows, and establishes new economic networks. We examine the validity of the theory through a comparative case study of Nordic political units from the dawn of the Viking Age to the end of the High Middle Ages (CE 800–1300), finding that raids, settlements, and conquests by Norwegian and Danish rulers in England, Europe's most advanced kingdom, set in motion state formation processes in Norway and Denmark. In these cases, the winners emulated the losers.