Chapter one first defines military intervention. It can occur with or without the consent of the targeted government and/or the United Nations, be direct or indirect, and be characterized as liberal and humanitarian. This section also situates military intervention among other seven other types of intervention: economic, political, cultural, institutional, legal, medical, and environmental. The following section discusses the theory of European military intervention, based on insights from realism, constructivism and post-colonialism. The realist approach is essential for explaining European intervention in Africa, as it takes account of motives such as security, economics, prestige and also, if an intervening state faces limited threats on these three counts, humanitarianism. Constructivism is used to uncover the norms of legality and Eurocentrism. Post-colonialism highlights the importance of history for the understanding of policy decisions on intervention, introduces the concept of neo-colonialism, and helps to address and refine the issue of Eurocentrism, which to date remains under-researched in the literature on international relations.