Frequently asked questions

Where does the data come from?

The map is built from primary-source letters and archival research, cross-referenced with place, campaign, and residency data collected and verified as part of this project's research pipeline.

Is the map free to use?

Yes — the core interactive map, campaigns, and place index are free to explore with no account required. Paid tiers will unlock the full letter archive and deeper residency detail.

How accurate is the mapped data?

Places are geocoded and cross-checked against the underlying correspondence wherever possible. A small number of places remain unmapped where coordinates could not yet be resolved — this is noted directly on the map.

Can I contribute corrections or sources?

Yes — reach out via the Contact page with any corrections, sources, or archival material you think should be included.

Where is my data stored, and who has access to it?

The service is built on an EU/EEA-only infrastructure stack, and data handling is described in full in our Privacy Policy.