Data and Methodology
The dataset used in this project is the Colonial Dates Dataset (COLDAT) , which records the extent and duration of European colonial empires. It provides standardized start and end years of colonization for all independent countries and their former colonies, enabling accurate comparisons across regions and periods.
The eight colonial powers included are Belgium, Britain, France, Germany, Italy, the Netherlands, Portugal, and Spain. For each country, the dataset indicates the colonizing power, the years of control, and the duration of colonization. Different calculation methods, such as the last recorded date versus the average of multiple sources, are noted and guided our choices for the visualizations.
These data enable a systematic analysis of the expansion and decline of colonialism. By examining how long a country remained colonized, by which power, and in which historical period, it is possible to identify temporal trends and patterns of imperial dominance while highlighting the diverse experiences of individual countries.
To prepare the data for visualization, we carefully analyzed every record, organizing it with pivot tables to detect patterns and ensure accuracy. This preparation allowed us to transform historical data into interactive visualizations that are clear, detailed, and faithful to the dataset.
Our approach emphasizes clarity without oversimplification. Each visualization represents both the temporal and spatial dimensions of colonialism, reflecting differences between colonizing powers and variations in colonial duration. This method combines rigorous data analysis with effective visual design to support exploration and understanding of a complex global phenomenon.
In the detail view, users can access a direct link to the Wikipedia page on each country’s colonial history. This feature aims to give visibility and recognition to colonized nations, highlighting their experiences and significance, and challenging the traditional focus on the colonizing powers.
For historical accuracy, all paragraphs providing context on colonial history and overviews of the colonial powers are based solely on the Encyclopedia Britannica . This ensures that the information presented is reliable, consistent, and grounded in authoritative sources.