The Horn of Africa (HOA) is one of the most troubled areas plagued by conflicts and security threats in Africa. At the heart of the underlying issues of the conflicts in present-day HOA, lie three inherited factors from the past: (1) the legacy of the Ethiopian Empire and its imperial expansion policy. (2) the legacy of European colonial rule and its policy of “divide-and-rule”; and (3) the legacy of external imperialist intervention after World War II and the support of undemocratic regimes in the HOA. However, the dilemma of insecurity in the region flows from the failure of the respective ruling classes to embrace good governance and from their weakness in effectively managing ethnic diversity. The main objective of this study is to identify the relationship between the internal dynamics of these conflicts, the regional and international interactions and their role in shaping the new geopolitical map of the HOA.