On the basis of published documents on the activities of the terrorist organization “Red Army Fraction” (RAF) in West Germany during the 70s-80s, the authors highlight the causes that led to the radicalization of the student movement and the transition of activists to the armed confrontation with the police in the name of “City guerrilla” concept. Among the documents mentioned, texts of the RAF members, their manifestos, etc. are avaliable, as well as the articles by one of the leaders of the organization, Ulrike Meinhof, which she wrote for the left-radical magazine “Concrete”. Also there authors used the materials of the German media. In addition, the authors have analyzed foreign and domestic historiography focusing on German-language studies. The conclusions, to which the authors of the article have come, can be summarized as follows. There were three main reasons for the radicalization of the German student movement in the late 1960s. Firstly, the protest spirit and antipathy towards the “conformist” older generation, caused not least by the fact that the governments of the Chancellors Adenauer and Kiesinger were associated with the rehabilitation of former Nazis, so left-radicals saw in their politics the returning of authoritarianism and the militarization of FRG. Secondly, the views of the leftist scholars (such as Herbert Marcuse, Theodor Adorno, Jurgen Habermas, and others) that were popular among young people and reflected, albeit exaggeratedly, the social problems of Germany at that time related to labor migration, property inequality etc. Thirdly, speaking of the internal political context, the authors have underlined the important role of the events that led to a creation of radical groups. Among these events the most important were the protest actions against so called “Extraordinary laws,” the beating of a peaceful demonstration by the police on the 2th of June and the killing of Benno Onezorge, the assassination of the leader of the student movement Rudi Dutschke, the occupations of universities in 1968 etc. Characterizing the foreign policy context, the authors figure out that in the conditions of the bipolar world and the unfolding of the Cold War, the German youth was inspired by the revolutionary movements of the Third World and also by the American youth movement against the war in Vietnam. At the same time, the future German “city guerrillas” were inspired by the images of Che Guevara, Mao Tse-tung, Ho Chi Minh, etc. There is no doubt that they were rather skeptic about the USSR, not considering it as a socialist state, while they were preferring Cuba or Maoist China, because at that time almost nobody was aware of an essence of the “cultural revolution” and Mao’s repressive policy. However, activity of left-radicals in West Germany was still profitable for the GDR government, controlled by Soviet Union, as far as they were trying to use every possibility to destabilize the situation in FRG.