If you called up two people at random in a particular country and ask them their ethnicity, what are the odds that they would give different answers? The higher the odds, the more ethnically diverse the country.
Five Harvard economists and social scientists set out to measure ethnic diversity and have mapped out the results. (see article)
African countries are the most diverse. Uganda has by far the highest ethnic diversity rating, according to the data, followed by Liberia.
Japan and the Koreas are the most homogenous.
European countries are ethnically homogenous.
The Americas are often diverse. Canada rate as more diverse than the United States or even Mexico.
Wide variation in the Middle East. The range of diversity from Morocco to Iran is a reminder that this part of the world is much less monolithic than we sometimes think. North African countries include large Berber minorities, for example, as well as some sub-Saharan ethnic groups, particularly in Libya. The diversity of Jordan and Syria are reminders of their internal complexity. Iran, with large Azeri, Kurdish and Arab populations, is one of the region’s most diverse.