Related Packages • jpmap

jpmap is intentionally named and designed as a Japan counterpart to usmap: users should be able to ask for a map, join ordinary tabular data, and plot a choropleth or point map without first becoming GIS specialists.

The package focuses on four things together:

an easy jp_map() / plot_jpmap() workflow;
visible Okinawa and Ogasawara inset maps for static plots;
prefecture and municipality boundaries through the same API;
explicit disputed-territory handling, including exclusion controls and highlight styling when needed.

Package Landscape

Package or project	Main use	Difference from `jpmap`
`NipponMap`	Simple prefecture maps and circle cartograms.	Prefecture-level only. Its manual notes that boundaries are simplified by hand and omit minor islands.
`jpndistrict`	Japanese administrative areas, offices, and reverse geocoding.	Historically important, but archived from CRAN. It does not provide a `plot_jpmap()`-style static map workflow.
`UchidaMizuki/jpmap`	Prefecture `sf` data and `layout_japan()` for `ggplot2`.	Prefecture-level only and GitHub-only.
`kokudosuuchi`	Download and read National Land Numerical Information data.	A data-access utility rather than an opinionated map plotting package.
`jpcity`	Municipality code and name conversion.	A useful companion package, not a boundary or map plotting package.
`jpgrid` and `jpmesh`	Japanese grid-square and mesh-code workflows.	Mesh/grid maps rather than prefecture and municipality choropleth maps.
`maps` and `mapdata`	General legacy map databases.	Not Japan-administrative-boundary focused; `mapdata` notes that its world map is outdated.
`geodata` and `rnaturalearth`	General global geographic data.	Useful for global context, but not a Japan-first plotting workflow.

There are also many small scripts and example repositories that show how to download a shapefile and draw a one-off Japan map. Those are useful examples, but jpmap aims to make the repeated workflow reusable.

Disputed Territories

Japan map packages handle disputed areas inconsistently. In a source and documentation check on June 14, 2026, the packages above did not provide a documented user-facing option equivalent to:

plot_jpmap("prefecture", territorial_disputes = FALSE)

jpndistrict source data includes rows for some Northern Territories municipalities, but that is not the same as an explicit disputed-territory layer with documented inclusion/exclusion controls, separate styling options, and documented source notes.

Users can remove disputed-territory shapes with territorial_disputes = FALSE, include only selected areas, or highlight them with disputed_fill and disputed_dots.

When To Use jpmap

Use jpmap when your goal is to publish or analyze a Japan map with ordinary R data:

library(jpmap)

plot_jpmap("prefecture")
plot_jpmap("municipality", include = "Okinawa")
plot_jpmap("prefecture", territorial_disputes = FALSE)

Use companion packages when they solve a more specific part of the workflow: jpcity for code conversion, kokudosuuchi for lower-level access to MLIT datasets, and jpgrid or jpmesh for grid-square analysis.