Scholars assert that the Cold War began at one of several different points. Material recently available at the National Archives yields a view different from those already presented. From these records, and material from the Foreign Relations Series, Parliamentary Debates, and United States Government documents, a new picture emerges. This study focuses on the British occupation of Germany and on the Council of Foreign Ministers' Moscow Conference of 1947. The failure of this conference preceded the adoption of the Marshall Plan and a stronger Western policy toward the Soviet Union. Thus, the Moscow Conference emphasized the disintegrating relations between East and West which resulted in the Cold War.

L’Organisation de la Coopération Islamique (OCI) créée en 1969 suite à l’incendie de la mosquée Al-Aqsa, représente la voix du monde musulman. C’est la deuxième organisation intergouvernementale après l’ONU regroupant cinquante-sept Etats membres aux quatre coins du monde.Un Programme d’Action Décennal (PAD) a été adopté lors du 3ème Sommet islamique extraordinaire réuni en 2005. Le PAD vise une nouvelle vision pour le monde musulman : « la solidarité dans l’action ».Cette thèse étudie l’évolution du rôle de l’OCI pour relever les défis politiques, économiques, sociaux et culturels qui surgissent sur la scène internationale et affectent la communauté musulmane. Elle met l’accent sur les points réalisés du PAD et les entraves de l’OCI à établir l’unité de l’Oummah islamique. / The Organization of Islamic Cooperation (OIC) has been established in 1969, following the fire of the Al-Aqsa mosque. This organization represents the voice of the Islamic world and it is considered according to its membership, the second intergovernmental organization after the UNO. OIC includes fifty seven member states coming from all over the World.A Ten-year Program of Action (TYPOA) has been adopted in 2005 during the third extraordinary Islamic Summit, aiming at establishing a new vision for the Islamic World called: « Solidarity into action ».This thesis discusses the evolution of the role of the OIC relating international challenges of political, economic, social and cultural nature that the Islamic communities have to face. The thesis points out the matters that have been achieved through the TYPOA and the obstacles that the OIC faced regarding the necessity to unify the Islamic Ummah.