The research project examines the history of immigration neighborhoods during the 20th century. It analyzes the emergence and transformation of such quarters as well as the negotiations over the arrival of immigrants for different neighborhoods in the German city of Hamburg. By examining the production and transformation of urban space as well as negotiations on migration in society, the project productively integrates approaches of migration history and urban history. The focus on the neighborhood level provides new perspectives, insofar as it challenges and critically discusses interpretations focusing on national developments or specific ethnic groups, which have dominated research so far.By looking at three selected neighborhoods, the project will examine the following fields in more detail: (1) patterns of settlement and segregation, the housing conditions of migrants and their role in processes of deterioration and upgrading of neighborhoods, (2) social infrastructures and institutions which structured processes of arrival and shaped the public appearance of arrival neighborhoods, and (3) the role of these neighborhoods for the development of the entire city, as well as forms of public perception and political regulations of the neighborhoods. It is assumed that the settlement of immigrants and the development of neighborhoods were results of negotiation processes in which, besides economic structures and political decisions, different social groups played a crucial role. The project will analyze these processes both on the levels of the city, the district and the neighborhood, as well as regarding different spaces inside a neighborhood – from private living rooms to spaces of public interaction and communication.The project examines the micro level of historical arrival neighborhoods for the first time for a German city over a longer period of time. It thus picks up international research approaches that have so far hardly been received in German historical studies. In the focus of interest are refugee and migratory movements, which were publicly treated as forms of immigration, but the project also takes forms of internal migration and inner-city mobility into account, if they had been significant for the development of a neighborhood. In order to point out continuities and turning points, recurring patterns and differences in the shape of the neighborhoods and in the local handling of migrants and migration, the study looks at a longer period of social change between the 1890s and 1980s. The focus of analysis will be on four phases of intensive immigration. Based on approaches of social history, political history and cultural history, the project works with a diverse sample of source material, in order to analyze the developments on the neighborhood level.