In the thesis the author on the basis of the relevant domestic and foreign literature, secondary and primary sources, and the logical relational complex displays and explicate the most violent period of the Soviet Union in its history of the October Revolution. It is the reign of Leonid Brezhnev, who has managed the state in its 18-year mandate. The period of this boiling diplomacy of the Cold War and the bipolar rivalry of the superpowers and their competition in armaments and military interference in the Third World. The paper further discussed the modus operandi of the Soviet leader as a cult of personality, and its positive and negative aspects of diplomacy and domestic politics, especially when it comes to domestic reforms and industrial production and competitiveness. The author quite rightly emphasizes diplomacy of the Soviet Union at that time, especially when it comes to the policy of Détente, relaxation of tension in international relations and reduction of armaments in a dead-heat, which lasts from the end of the most destructive war in human history. Brezhnev period will be marked with an earlier intervention in Hungary and East Germany two major interventions, one in Czechoslovakia and Afghanistan whose external and internal factors bring in the work and have special sections, as well as social status and cultural characteristics of the population in this period.