When the Cold War ended, the existing global political alignment yielded to new regional relationships in which many middle powers exerted increased influence. Increasingly assertive middle powers, countries with significant economic influence either in relation to their neighbors or in broader trade networks, jockeyed for regional leadership.

While the end of the Cold War reduced superpower pressures that intensified regional conflicts, other factors continued to feed conflicts around the world. In the 1990s civil wars in Bosnia, Kosovo, Rwanda, and Afghanistan killed over a million people and created hundreds of thousands of refugees. Since 2000 new and continuing wars have caused millions more deaths and new refugees. Rivalries between ethnic groups often lay at the heart of these wars.