In this paper, we present a database and an interface on text reuse between newspapers and journals published in the Swedish language in Sweden and Finland during the 1645–1918 time frame. Using two national, digital newspaper collections, we detected their textual similarities with a computational method to study the textual migration, i.e., information flows, between the two countries. For purposes of this project, we developed a database of detected clusters of text reuse and an online interface to search, examine and analyse the transnational movement of information. The database, Text Reuse in the Swedish-language Press, 1645–1918, is accessible online and includes texts from over 1,100 newspapers and journals published at approximately 150 locations at various times during the 274-year time frame.