Introducing COLDAT: The Colonial Dates Dataset

Social scientists increasingly turn to historical research to understand long-term institutional and societal change. However, data availability and quality, including disagreements about basic historical facts, remain central challenges to this line of work. When it comes to research on European colonial empires and their legacies, social scientists draw on a number of secondary sources, which differ in scope, detail, and coding decisions. Thus, findings risk being driven by the choice of the data source rather than substantive differences. To address this shortcoming, I introduce the Colonial Dates Dataset (COLDAT), which aggregates information on the reach and duration of European colonial empires from renowned secondary sources. By aggregating secondary sources, rather than collecting from primary sources, the new dataset reflects the accumulated knowledge in the discipline and relieves researchers from making hard to justify choices between different historical datasets.