Notes on the data
The map is a choropleth of whole modern countries, so a shaded nation was
touched by the empire — not necessarily covered end to end. Only coastal
Algeria was Roman; only eastern Afghanistan was Mughal; only the Ili valley of
Kazakhstan was Qing.
Extents are approximate maxima and were sometimes reached at slightly different dates
from the year given. Land areas are the figures most often cited for greatest extent.
Population figures are scholarly estimates — for the ancient empires they are
ranges rather than facts, and reasonable sources disagree by a factor of two.
Base geometry: Natural Earth 1:50m map
units, projected to Natural Earth I and baked to SVG at build time. Share of world land
is measured against 148.9 million km².