This chapter explores how emporia could have operated within the political and legal institutions of early medieval Northern Europe. I examine documents and narratives to suggest how prevailing models have misconstrued the norms and institutions of power used to govern these places. The emporia, I argue, were essentially part of a social organization designed for dealing with strangers who came from outside regional social networks and cultural groups, and that existed within a society governed ultimately by common law and popular assemblies. In the absence of the chartered towns, guilds, or individually granted privileges that secured the rights of travellers in the High Middle Ages, emporia were attuned to a simpler framework, in which wider agreements had to be made at group-level and then ratified at legal assemblies. As such, they operated as havens for foreigners who formed a permanent diaspora away from their own country. They were entitled to comply with their own laws within a circumscribed space, and to answer collectively to regional authorities.

This chapter focuses on the entanglement between people within sites. Analysing evidence for specialized crafts in emporia, it asks why craftspeople went there, and how they contributed to make these places into hubs of particular social networks. It issues from the key observation that crafting activities in emporia were not only dependent on far-flung networks with other locations, but also on entangled webs of people and processes within the immediate community. The need for access to raw materials, opportunities for learning, markets and, perhaps more than anything, the need for collaboration between specialized artisans, was a decisive incentive for strangers to congregate at specific sites. Craft workers in emporia were dependent on these different elements to practise their trade. As a by-product, their work was able to bridge social relationships, which contributed to the social capital of an otherwise inconsistent community. Such interactions thus gave an unprecedented prominence to weak social ties in the intersections of roles and personhood in individuals, and, more broadly, at the level of the assemblage.

This chapter introduces the book as a textbook about the stochastic actor-oriented model. This is a statistical model for analyzing network dynamics for data given as two or more repeated measurements of networks, possibly together with other actor-level outcomes. After positioning this book in the literature, the chapter mentions “Ties have consequences” as a leading principle of this methodology and relates this to the concept of endogeneity: Some of the variables under consideration are, at the same time, both a dependent variable and also an explanatory variable for another dependent variable. At the end, a brief description is given of the kind of data required for this model.

This final chapter draws together the arguments established in the book and outlines further perspectives for our understanding of the role of weak ties and strangers in human societies in both the past and present. It explores the northern emporia in the context of a global, comparative frame to understand in what ways they compare and contrast to developments elsewhere in the Early Middle Ages, and to urban networks in other periods. I review how emporia compare with other trading institutions in a broader historical framework. To this end, I point to the central but widely misconstrued role of encounters with strangers as part of human sociality. The conclusion points to a reality that lies deep within the history of social networks, which have been widely disregarded in archaeological models and social theory, but which in fact make sense of historical trajectories and the path to the present world.

The chapter explores how engagements with strangers were established in the early medieval emporia in Northern Europe, and how trust was created from the ‘weak ties’ of social networks in these meeting places. It has its foundations in the archaeological record, which is contextualized in a broader geographical and temporal framework. Focusing on themes such as maritime mobility and interaction, scale and organization of transport, modes of trade and exchange, extraction and circulation of materials, crafts and specialized urban production, and the cultural interactions of urban communities, the chapter debates how the findings of Viking-Age archaeology may hold important implications more generally for those studying the development of urbanism and the history of human societies. It also considers how emporia operated as an aspect of social networks beyond regional groups and polities in the non-state societies of early medieval Northern Europe, and how aspects of social networks can account for the development of these centres.

Abstract: The chapter engages Horden and Purcell’s revision of Braudel’s Mediterranean model to seek a more dynamic account of Christ religion in its Mediterranean contexts. Critiquing earlier portrayals that examine Paul through a Mediterranean lens, it offers a more nuanced account through exploration of fictional social networks and geographical itineraries found in Acts, as well as in both the undisputed and disputed Pauline letters and apocryphal acts. The journeys described in Acts and implied by Paul’s letters offer a panoramic Mediterranean view, akin to ancient imperial maps, envisioning a world shaped by itineraria of early Christ travellers. Employing David Sacks’s insights, the essay examines Paul’s territorial concept of the Mediterranean, controlling people and regions through an imagined geography connected by messengers and audiences. Paul’s letters condense the Mediterranean by using vivid imperial imagery and language, revealing alignment and distinction from the Roman Empire. Integrating anthropological insights on gift-giving, Paul’s Mediterranean is seen as a shifting and dynamic phenomenon challenging patronage norms, fostering social cooperation, and economic solidarity.

Agent-based modelling (ABM) in social networks offers a powerful framework for simulating individual behaviours and emergent collective patterns within dynamic and interconnected populations. This chapter explores the conceptual foundations, methodological innovations and behavioural implications of ABM in the context of social networks, with a particular focus on the modelling of communication, influence, cooperation and contagion. Drawing from the fields of behavioural science, network theory and computational social science, the chapter presents ABM as a generative tool for understanding how micro-level decision-making rules produce macro-level phenomena. It also critically evaluates the increasing use of AI-driven agents – including large language model (LLM)-powered agents and synthetic personas – in simulating realistic and context-sensitive behaviours within artificial societies. The chapter engages with ethical and methodological challenges, including representation, explainability and the problem of behavioural validity. A worked example is included, illustrating how agent-based simulations can be applied to study misinformation diffusion and norm formation in online social networks. Ultimately, the chapter argues that agent-based modelling in social networks not only advances Behavioural Data Science methodologically, but also fosters new forms of interpretive insight into the dynamics of collective behaviour in an age of digital mediation.

Sancho’s Letters begins with an extensive list of “Subscribers Names,” crediting 1,181 individuals who financed the book as a source of funds for Sancho’s widow and children. This chapter examines that list and the process of publishing “by subscription,” highlighting Sancho’s differences from other 1782 subscription publications and the later Black British authors Olaudah Equiano and Ottobah Cugoano. In Sancho’s list, the variety of honorifics associated with each name reveal that the book’s supporters came from a broad spectrum of social ranks – and that a strikingly high percentage of them were women. Several specific individuals are discussed to illustrate the motives of Sancho’s subscribers: patronage and clout; friendship and philanthropy; and abolitionist politics. Despite the later embrace of Sancho’s book by abolitionists, this chapter contends that its subscriber list is more strongly shaped by a sentimental literary milieu and the social ties of the book’s editor.

Laplace operators and their spectral properties are powerful tools for the analysis of networks in the social and the biological sciences and in other domains. In computer science, the theory of families of expander graphs is particularly important. Eigenvalues are also a key for quantifying synchronization and other features of nonlinear dynamics.

Chapter 14 examines how the rise of American philanthropic foundations – particularly the Carnegie Endowment for International Peace (CEIP) – shaped international law during the League of Nations era. Although the United States government remained formally outside most League institutions, American influence was felt as private organizations brought their considerable resources to bear on the development of the social sciences, including the discipline of international law. The chapter explores how the CEIP’s legal philanthropy sustained international law as a transnational professional practice linking League officials, judges, academics, and practitioners. Drawing on archival research from the League of Nations and the CEIP, as well as a dataset of roughly 25,000 individuals affiliated with League bodies and related NGOs, the chapter addresses several key questions: What strategy guided the Endowment’s funding decisions? How did this strategy interact with broader geopolitical dynamics, particularly the ambivalent US–League relationship? And how did recipients leverage foundation support to advance their own agendas? The chapter traces the CEIP’s project of replacing a militarized global regime with a rules-based international order administered by trained legal professionals but also offers insights into the structural impact of philanthropic funding on the sociological makeup of the legal profession in the League era.