The main idea of this Thesis is the survey of the practices of humanitarian intervention under international law in general,and in particular international humanitarian law,to protect civilian populations and the safeguarding of their dignity in the event of a conflict in Africa.The current debate on humanitarian intervention,due to the proliferation of armed conflicts within States in Africa,is taking place in the context not only of new actors but also of new sets of issues relating to the suffering of victims.The record of death,injury,displacement and other destruction of property that those conflicts inevitably entailed is terrifying in terms of the facts and the legal arsenal developed since the Charter of the United Nations to prevent them.At the heart of the debate is the practical question of whether a foreign intervention,by other States and international organizations,can be used for good in Africa in conflict situations causing the commission of international crimes.By focusing on practices in Africa,and especially the experience of the Rwandan genocide and the cases of Sudan and Libya,this study seeks to explore the failures of the international community,the African Union in implementing their strategies to protect populations from atrocities.It addresses the question of whether the inconsistencies,weaknesses,and lack of timely impact on the part of the international community and the African Union have created conditions that have contributed to some of the worst human rights violations,leading in some cases to genocide and growing insecurity.Responses to these tragedies call for international responsibility,which is a set of consequences related to the breach of international obligations,that is,the legal bond by which a subject of international law is required,towards one or more other subjects,to engage in a particular conduct or to refrain from engaging in a certain conduct.This responsibility commits the sovereign States to protect their populations from serious human rights violations and inhuman acts.If there is illicit behavior such as genocide and ethnic cleansing,crimes against humanity,war crimes and other severe violations of human rights,the international community must intervene under the name of "humanitarian intervention" in the fulfillment of the responsibility to protect civilians.Consequently,the sovereignty,non-interference in the internal affairs of the State and non-use of force that govern international relations are in practice called into question to the detriment of the failed State to protect the civilian populations of that State in situations of a grave humanitarian tragedy.This thesis goes beyond the antagonism between sovereignty and intervention.It analyses the legal problems related to the concept of humanitarian intervention in international law from the points of view of classical and liberal doctrine.Here,the practices of the Charter of the United Nations,its derived norms,the 2005 World Summit Outcome Document and the Constitutive Act of the African Union solve this problem with legal arguments.Indeed,it examines the political and institutional measures developed by African states through the African Union to prevent and deter serious human rights violations in its member states.Secondly,this research examines the practices of intervention by the use of force following the criteria of the classical doctrine and ICISS.Finally,it analyzes the intervention of international organizations,NGOs and international jurisdictions in the protection of civilians in countries of conflict in Africa.Chapter One is an overview of legal issues on a humanitarian intervention under public international law.It begins analysis of the doctrinal controversy over the definitional concept of intervention that is likely to challenge the principle of state sovereignty.It demonstrates the difficulty of reconciling the two concepts,the need to protect civilian populations against severe human rights violations,the obligations of the State and the international community in the protection of human rights.Thus,the failure of the State to respect its internal obligations would limit its sovereignty for the benefit of the international community.Chapter two seeks to find a legal basis for humanitarian intervention through state practice,contemporary international law,and African regional law.It examines past practices up to the emergence of intervention under the UN regime,regional bodies and ICISS.Indeed,this emergence makes it possible to specify the scope and the types of interventions that can be envisaged: forceful and unforceful.Chapter three examines the preventive policy measures envisaged by the African States through the African Union and regional mechanisms.These measures draw on the AU’s institutional and policy framework for protecting civilians,conflict management through the African peace and security architecture,and post-conflict reconstruction and development.It recapitulates the political and institutional commitment of Africa’s subregional economic communities to the process of intervention and peacebuilding through the Economic Community of West and Central African States.However,political challenges and their financial dependence on external partners often affect the outcome of the actions undertaken.Chapter four provides an in-depth analysis of the practice of humanitarian intervention by armed use in Africa under the African Union and the United Nations.It argues that the principle of non-interference should be questioned and that military intervention should be subject to precise criteria.Depending on the cases studied,it exposes the weaknesses of the AU in accomplishing its missions in its Member States,the delayed and inadequate reaction of the UN about the criteria for armed action.It proposes possible solutions to the weaknesses of the African Union and the United Nations.Chapter five deals with the practices of international organizations,NGOs and international jurisdictions in Africa.It focuses on the system of protection of individuals in Africa by the UN Human Rights Council,the Office of the High Commissioner for Refugees and the International Committee of the Red Cross.It then analyses the involvement of ad hoc and permanent tribunals in the process of protecting civilian populations in Africa and their impact on peacebuilding and the fight against impunity in Africa.Chapter Six summarizes this research by noting the weaknesses of intervening actors and the difficulties related to the implementation of humanitarian intervention.It provides recommendations to the international community and the African Union so that the actions of the intervention can effectively respond to the needs of the civilian populations of the concerned State and save as many lives as possible from mass death.