The spread of a war or an empire over time

The EU's members revealed in the order they joined, from a dated list in Areas and borders.

• Countries by date: Elements → Areas and borders → Several at once: "Poland 1939", "France 1940", "Italy 1943"… one per line, Dates over (s) 8: each country reveals in date order. With Atlas MCP: highlight_countries with dated lines (countries: ["Poland 1939", "France 1940"]).
• Areas from a file by date: import a GeoJSON of fronts or historical borders as Editable paths with Appear by a date property. A folder of yearly files (world_1938.geojson, world_1945.geojson) → Read all N as a time series.
• Events: a table of events with dates and positions (UCDP, ACLED exports) as a Heat map that grows by date, pins that appear by date, or particles (events, Pulse).
• Movements: a table of origin, destination and year → Arcs, Draw on by the year.