The chapter sets out the material conditions and social structure of the hunter-gatherer era, emphasising the role of kinship, mobility, egalitarianism and trade. It sees the material and social structures as relatively stable then looks at the long transition between the hunter-gatherer era and the era of congolmerate, agrarian/pastoralist empires, emphasising climate change as the key to population growth, settlement, technological change, and the shift to agriculture. It notes the shift from biological to social evolution, and the link between settlement and a move away from egalitarian relations. Agriculture reinforces settlement rather than causing it.

The chapter sets out the story of the era of agrarian/pastoralist empires (CAPE) in terms of its material conditions and social structures. New materials were hard metals and gunpowder. New sources of energy were wind and animal power. New technologies were the sailing ship, wheeled vehicles, writing, money and paper. Society became much more complex and larger in scale, and developed many new institutions, notable amongst which were human inequality (slavery, patriarchy, economic, monarchy, dynasticism), universal religions, empire, territoriality, sovereignty, trade and diplomacy. This package of material and social conditions proved remarkably stable up to the end of the eighteenth century AD. The core military dynamic of this era was between militarily superior nomadic steppe peoples, and more numerous and wealthier sedentary civilisations.

How will the third phase of the transition to modernity unfold? One way of approaching this question is through the five possible pathways for the human species set up in Chapter 1. From that perspective, there is an emerging dialectic between the ongoing push for species empowerment that has defined humankind’s path for thousands of years, and the danger that path raises of species suicide, replacement or regression. There is not much point in dwelling on the options and scenarios for species suicide, extinction or replacement. The first two simply end the story. The third might well divide opinion on whether species replacement is part of the problem or part of the solution. Replacement could come in various forms, with no way of predicting which. It is anyway beyond my capacities to work out what the material capabilities and social sensibilities of a superior intelligence to ours might be. That leaves the option of exploring how humankind might try to stay on the path of empowerment, while adapting to the mounting environmental constraints it now faces.

Chapter 3 has set out a sufficiently full sketch of CAPE society to provide a good sense of what the nineteenth-century turn towards modernity was a transition from. The questions to be answered in this second part of the book are two. First, what was that transition to? In other words, what is ‘modernity’? And second, what was the nature of the transition itself? It is clear that the CAPE era ended. But it is less clear that modernity has properly or fully begun. Are we still within a transition period somehow parallel to that between the hunter-gatherer and CAPE eras? Or has history accelerated so much that the transition was very quick, perhaps only a few decades, and we are now fully into the modern era? What did the shift out of the CAPE era towards the modern one involve, both materially and in terms of social structure? How did this shift unfold over the last two-plus centuries, and where are we now? This sets up for Part III, which looks at where this unfolding seems to be heading.

The two chapters in this section serve as the prelude to the discussion of the transition towards modernity that occupies the bulk of the book. In order to understand modernity, it is necessary to understand the cumulative building of global society over the two eras that preceded it: what each did and did not contribute to the one that followed it. Without understanding the material conditions and social structures of each era, it is not possible to get a clear view of the transitions between them, what got carried forward and what not, and what the changes were. These two eras are, of course, interesting in themselves when viewed in this perspective, but the immediate purpose of analysing them here is to set up the historical flows that led to, and into, the transition towards modernity. A second purpose is to lay the groundwork for the comparative study of eras, though that is only lightly followed-through in this book.

In the Conclusions to Chapter 3, working with the advantage of hindsight, I focused on the end of the CAPE era, its successful, if tenuous, connecting up of the whole planet by trade, and the precursors of its transition towards a new era of modernity. I looked in particular at the leading role of merchants and commerce in realising dreams of universality beyond the reach of any empire or religion, albeit mainly in the economic sector and not in the political and societal ones. I posited that the great achievement of the CAPE era was to achieve the first conscious globalisation, but that given the limits of technology and energy resources, this could only be done thinly. That pointed forward to the intensification of globalisation as the likely next step for humankind after the CAPE era. The four chapters in Part II could easily be read as fulfilling that expectation. Especially in material terms, globalisation was hugely intensified. The social picture is much more mixed, but can also be read as intensifying globalisation. It is absolutely clear that by the late eighteenth, early nineteenth century, the CAPE era was over. The question is how to read what followed it: as the opening of a third era, modernity, or as the opening of a period of transition between the CAPE era and an emergent modernity?

The chapter sets out the material conditions of the transition from the CAPE era to modernity, seeing a transition from the limited energy sources and materials of the CAPE era, to the more or less unlimited energy sources and materials that came into play during the nineteenth century. It looks in detail at the technological developments of the transition period since the early nineteenth century, and at the huge increases in interaction capacity and powers of destruction that these enabled. In material terms, the circumstances of humankind were transformed, but with the costs that the carrying capacity of the planet was overburdened, and humankind put itself at risk of committing species suicide.

The chapter continues the analysis of social structure in the transition from the CAPE to the modern era, but looking at the institutions that emerged within the transition period itself. It looks at the synergies and contradictions within the unfolding institutional structure of modernity, and contrasts this turbulence with the relative harmony in the institutional structure of the CAPE era. Each institution is analysed for how it works across the three domains: interhuman, transnational and interpolity/state.

The chapter opens the analysis of social structure in the transition from the CAPE to the modern eras by reviewing the primary institutions carried over from the CAPE era into the transition, seeing which became obsolete, and which adapted to the new conditions and survived. It constrasts the relative simplicity and straightforwardness of the material developments during this period to the complexity, contradictions and turbulence of the social structure.

The chapter draws together the main conclusions from the study. It highlights the implications of this study for how history is analysed and periodised, and how the approach taken in this book offers opportunities to create common ground amongst those interested in ’big picture’ approaches to the study of humankind in Intnernational Relations, Global Historical Sociology, and Global/World History. The chapter also looks at the implications for the English School of extending its analytical scheme in this way.

There is a considerable amount of historical momentum behind the move into deep pluralism. Structural shifts such as the wider distribution of wealth, power, and cultural and political authority, the fading out of superpowers, and the rise of regionalism are hard to stop. Points of historical baggage such as introverted great powers, post-colonial resentment, and the normative crisis of liberalism and its teleology also run deep. The power-shift currently underway is much deeper that just between the US and China. It is about the ending of two centuries of Western-dominated, core–periphery, world order, and the opening of a multi-civilisational one. Although deep pluralism could in principle take a consensual form, under these circumstances it is not all that surprising that at least for now it is taking the contested one. This will happen regardless of whether the US–China rivalry turns out to be global or inter-regional.