In the mid-2000s, I began to work with George Lawson on the question of periodization for International Relations (IR) (Buzan and Lawson, 2014a, 2015b). That work was mainly focused on moving away from the excessive military-political benchmark dates favoured by mainstream IR. It developed the idea that benchmark dates needed to be looked for across all the sectors, not just military and political, and that major benchmarks would consist of clusters of different events across the sectors. That approach is continued here.

Even before that, I was working with Amitav Acharya to promote more global approaches to thinking about IR (Acharya and Buzan, 2007,2010, 2017, 2019; Buzan and Acharya, 2022). Prompted in part by conversations with Tarak Barkawi about periodizations from a Global South perspective, I began to pull these two threads together when working on the book that became Making Global Society: A Study of Humankind across Three Eras (2023). But the chapter on periodizing for Global IR became too long, within a book that was also getting too long. It was not necessary to the core argument of the book, and was taking on a life of its own. So I extracted it from Making Global Society, and began to treat it as a separate project. This book is the result.

The idea for periodizing the military sector under modernity in the way done in Chapter 2, and some of the ideas that follow, came out of discussions with Tarak Barkawi. I am profoundly grateful for his insights, without at all committing him to the interpretation of them unfolded here.