The present research aims to bridge the diverse cultures of the Baltic region through reconstruction and analysis of cross-national urban heritage created during the shared history of their coexistence and interaction since the late nineteenth century. I intend to reveal, map, and analyse the urban heritage that Swedish and Finish architects had formed in St. Petersburg since the late nineteenth century and up to the Bolshevik Revolution. In the last decades of the nineteenth century, the Russian Empire entered the stage of intensive economic development, attracting international investors, including Swedish businessmen. Settling and developing their business in St. Petersburg, these entrepreneurs provided commissions to their compatriot architects, such as Carl Anderson, Fyodor Lidvall, and Henry Johnson among others. After the Russian revolution of 1917, many architectural projects initiated by the European commissioners were interrupted, while the completed ones suffered from nationalisation, destruction, and neglect, which explains the poor state of the remaining objects. This applies primarily to industrial architecture and workers’ settlements in St. Petersburg, which were built for the Swedish corporations: e.g. factories, office buildings and residential complexes of the mechanical plant ”Ludvig Nobel” and the telephone factory ”L.M. Ericsson & Co. ” Despite their utilitarian nature, these industrial and housing ensembles serve as vivid examples of Northern Modern and proto-functionalist architecture. These projects resemble early experiments with the rational organisation of the working space inside the factory workshops on the one hand and introduce innovative solutions for workers’ housing on the other. During the Soviet period, the industrial architectural sites built by foreign entrepreneurs had been introduced neither to the academic/architectural community nor to the general public as artistically, historically or culturally valuable heritage. This has led to a critical current state of these objects and a lack of knowledge not only about their existence, but also about the general long history of cooperation between Sweden and Russia, which developed in various areas of economic and cultural life in the region before the Revolution. The proposed research project covers the disciplines of aesthetics, urban, cultural, and memory studies, of heritage preservation and history of architecture.