The purpose of the study is to analyse how the United Nations has reacted to foreign military interventions and which factors can help explain the reactions. In order to carry out the investigation the term foreign military intervention is defined, criteria for the selection of cases are formulated, and cases selected. This is followed by an examination of the United Nations’ reactions to the selected cases through the Security Council’s and the General Assembly’s responses to the interventions. The next step of the analysis is the formulation of a Hypothesis. This is done from a legal and normative approach to explaining the United Nations’ reactions. The Hypothesis is operationalised and tested through the formulation of two specifications. The two specifications are analysed in the context of the United Nation’s reactions to the selected cases. Based on this analysis the validity of the hypothesis is assessed.