This article analyses the formation and early development of Copenhagen, Denmark, through the methodological concept of biography. How can we understand the development of the town from a small, anonymous port in the eleventh century to the successful merchant’s town that it was in the thirteenth century? Which people, events, and wider processes in society had impact on the development of early Copenhagen? In this article, a biographical approach is used as a way of looking at the development from a contemporary perspective, considering actors and processes involved in the first settlement without seeing it through the prism of the later ‘result’ — the medieval merchant’s town. This can hopefully give a more nuanced understanding of the actions and events of importance for the development of the town and contribute to an understanding of the course of medieval urbanization as an unpredictable process without a given ‘result’. The study takes its starting point in the new archaeological information revealed in Copenhagen in later years, which together with the re-examination of older archaeological material, historical sources, and new ways to statistically model radiocarbon data present a picture of a dynamic initial period of the town, with several actors involved in the course of events shaping the town.