A number of scientists studied the social and psychological situation of the peoples of Europe after World War I, has faced many of the peoples of Europe, psychological and social problems as a result of that war, which has millions of their lives there. The tragedies of that war have left the social effects on people fighting, which led to the emergence of social psychology in an attempt to study the psychological factors Assembly for a large number of people. We have different people during the war on Some were caused by driving and driving and the other national defence of the interests of colonial or without motive, but Forced to participate in the war, which affected and caused many tragedies, making many ignorant of the causes and consequences thereafter, according to numerous studies. We have different concepts and values, as a result of the First World War was won, communism in Russia and a large number of security in the West, while Sharp large number of people to extremism in political thinking as a reaction to the war and especially in the conquered countries, which has been deployed by Nazism and fascism dependent Dictatorship and violence as a means of governance and application, resulting in a decline in support of liberal thought, which was unable to prevent the outbreak of the first war, or stand firmly in front of dictatorships based on the rising despair and defeat the mass of poor economic conditions or the devastating social effects of war, which left a large number of families without a breadwinner Or loss of a large number of young people are causing the imbalance of population and the prevalence of a state of instability to the psychological and social strata of society which have become in conflict instead of uniting to build the nation and became wrong way to build the homeland is the prevailing goal dictatorship and symbols. The political changes resulting from the emergence of collective thinking on one goal, but different motivations to achieve that goal and, by contrast, has become the opposition to collective thinking particularly vulnerable to those that are characterized by violence and racism. One of the consequences of war, is twice the feudal classes and middle classes, while the gap between rich and poor, and the emergence of a state of public discontent to those who fought in the war did not receive the benefits or services compensates. Has suffered from war victors and defeated, and occurred in the period between war political turmoil in Europe, cases of non-indifference and widespread corruption, freedom from social constraints prevailed in the victorious States, which did not wish the outbreak of another war, while the case of States defeated completely different, they are in a state of readiness For revenge, the military mobilization in the extreme situations help form the ideological extremist nationalism tends to racism and contempt for other peoples. The situation was terrible, it was the absence of reason and logic, and in several studies shows us the impact of community mobilization in the individual who loses his identity and freedom under repressive regimes are fighting democracy and freedom and calls for relinquishing the individual in society and way of building strong state for all its rights and hopes. There has been participating in the States that embrace ideologies competing with each other, the absence of official awareness among people under Nazism and fascism are the same as existed in the Soviet Union, dictatorships are similar in content despite the different forms, and that they will occur among the horrible process, a violent clash that is End genocide different ethnic groups and under various names.