Periodized WHEP polity database imported from the whep-polities
repository.
Format
An sf data frame where each row corresponds to one territorial polity over a continuous time interval. Key columns include:
polity_code: Stable WHEP polity identifier, usuallyPREFIX-start_year-end_year.polity_name: Human-readable polity name.start_year,end_year: Inclusive validity years for the row.iso3_code,iso3c: ISO3 code where one exists.iso3cis retained as a compatibility alias.polygon_status: Polygon status inwhep-polities("assigned","proxy","missing", or"excluded").has_geometry: Logical flag indicating whether the geometry is non-empty.geom: Multipolygon geometry.
