This article examines the global sources of regional transitions from war to peace in two types of region: unstable (war-prone) and stable (not war-prone). I argue that the sources of regional hot wars are regional and domestic rather than global. Similarly, the possibility of reaching a high-level 'warm peace' (i.e. conflict resolution) depends on regional and domestic forces. Accordingly, there is only limited influence of competing great powers on stable regions which are not war-prone. Yet, global factors can make a difference with regard to unstable war-prone regions depending on the type of great-power engagement. The great powers can bring about a lower level of 'cold peace' through conflict reduction if the great-power intervention in war-prone regions is hegemonic or cooperative. If, however, the type of great-power regional engagement is competitive, then the great powers play a permissive or even aggravating role with respect to the local violence in such regions. At the same time, great-power competition can bring about regional-war termination, which, in the absence of effective conflict resolution or peacemaking, leads to a regional cold war. Great-power hegemony or concert can also increase the likelihood of a transition to warm peace in stable regions, especially if they are populated by young democracies. The article applies the thesis to regional-war termination by the superpowers in the Middle East during the Cold War era. I also discuss the effects of US hegemony on the emergence of cold peace in the Middle East. The pacifying effects of great-power concert and hegemony were also shown in another war-prone region - the Balkans during the 19th and 20th centuries. Finally, both the contribution of international factors to regional peace, and the limitations of this contribution, can be seen in the post-World War II transition of Western Europe to warm peace.