This work attempts to seek new insights in understanding the archeological phenomena traditionally labelled as the western Bronze Age and the coastal Pre-Roman cultures of Finland (1500 BC-AD 1), by studying the phenomena from a socioeconomic interaction and practice oriented community perspective. The basic line of thought is that it was the everyday life of the local agents and their interactions that constituted the local communities. Communities are seen as built from the bottom up by the interaction of various local agents. The organised agents, their practices and their mutual interaction on various scales of social organisation are regarded as the central factors that created and shaped the history of the communities. Problems that are addressed concern the interrelationship between the subsistence practices, habitation practices and the social organisation of the coastal communities. Houses and local polities are regarded as two basic social institutions that were essential for the structuration of the coastal communities and for their relation to external networks. I also address the issue of the various spatial and temporal scales that can be considered as essential for the structuration of the coastal communities, and furthermore how the coastal communities managed change over time. The geographical scope of this thesis is limited to the former province of Vaasa (Vaasan lääni/Vasa län) in western Finland, with a special emphasis on the coastal southern part of Ostrobothnia.  A suggested high-rank House from the Late Bronze Age is studied in Laihia. Methodologically a broad perspective with a comparative, diachronic and a multi-proxy approach is conducted in the study of the structuration of communities. The constitution of the communities is largely approached through themes that are related to landscape and settlement archaeology. Contextual analyses of the combinations of various subsistence and habitation practices form the basis for the identification of different community constituting subgroups of agents.