Origins of the transitology concepts Earlier contemporary eras were dominated by colonialism (the late nineteenth and early twentieth centuries), wars (the two world wars and the decolonisation wars for most of the first half of the twentieth century) or ideological competition (the second half of the twentieth century with the Cold War). Whether democratisation evolves in waves or causally-related sets of transitions is debatable, primarily because it is difficult to discern one wave from the next. Is there a contagion effect that spreads ideas across borders? For example, the Arab Spring had been preceded regionally by the collapse of the regime of Saddam Hussein in Iraq by force in 2003 (again, to better or ill effect2), and major countries such as Indonesia witnessed transitions from authoritarian to democratic regime type in the late 1990s following the collapse of the Suharto ‘New Order’ regime in 1998. Since 1989, the world has arguably been experiencing one large and extended moment of global transition unpacked in three different, yet equally consequential, moments generating transitions: post-Cold War in the 1990s, post 11 September in the 2000s and post-Arab Spring in the 2010s. Indeed, these three phases were preceded by ‘re-democratisation’ in the Americas, notably Argentina, Brazil, Chile and Peru. It was in these cases that now common concerns with issues of transitional justice (which in turn had precedence in early cases, notably in post-World War II Germany and Japan) in particular emerged together with mechanisms that proliferated globally such as truth and reconciliation commissions. It was also in the study of these phases that crucial insights were gained into the role of social movements in toppling control by military-led ‘bureaucratic-authoritarian’ regimes, and aspects of the transition such as the role that pacts between the military and the opposition played in the course of transition.