This chapter outlines the geographical and chronological contexts of the Byzantine sphere, stressing the role that terrestrial and maritime geography played in the relationship between the imperial centre at Constantinople and the frontiers, as well as in diplomacy. It charts gradual territorial expansion, growth in the economy and flourishing of the church, particularly monasteries, between c.700 and 1050, followed by imperial collapse in the eleventh century, the consolidation of a smaller imperial space in the twelfth and political fragmentation thereafter. It considers the role played by societies and polities beyond the empire in the wider Byzantine sphere, a sphere far from culturally homogeneous. Attention is paid to the principal political formations within the empire itself, emphasising the relationship between formal and informal power. The key co-ordinates of formal Byzantine political society – emperor, palace, eunuchs, bureaucracy – are identified, but attention is also paid to those whose agency in political life was highly significant, if less frequently discussed: kinship and friendship networks, women, urban communities and charismatic holy figures.

The Conclusion sums up by establishing patterns of how actors order different parts of an arena and create security. It presents the key findings along the four dimensions of the historical legacies of centre–periphery relations, distinctions between inner and outer circles, competition or complementation between stable and fluid ordering forms, and embedding or detaching interventions. My analysis contributes novel answers to questions about local security in conflict-affected countries and an original framework capable of facilitating future comparative analyses on the matter.