Asia and Africa are the most densely populated regions.
Africa is already more densely populated than Europe - if one includes the Russian Federation in Europe. This may surprise people who imagine Africa as an "empty continent". But Africa includes large inhabitable, and almost unhinhabited areas, such as the Sahara or the tropical rainforests.
By the end of the century, Europe may be more sparsely populated than Latin America and the Caribbean - due to Europe's projected population decline.
However, huge differences in population density exist within these regions. See next slides.

Currently (in 2014), Southern Asia, the Caribbean and Western Europe are the most densely populated sub-regions.
Eastern Europe, Oceania and Australia / New Zealand are, by far, the most sparsely populated sub-regions. Most likely, this will not change over the next 90 years.
By 2050, Western Europe will no longer be one of the top three most densely populated sub-regions. Instead, South Central Asia (primarily due to India) will "move up" to the position of the second most densely populated sub-region.
By the end of the century, Southern Asia, Western Africa and Eastern Africa will probably be the most densely populated sub-regions in the world.

The figure above presents the 50 most densely populated countries with a population of 5 million or more in 2015. (Only the city-states of Singapore and Hong-Kong are excluded.)

Top of the list are Asian countries, such as the Republic of Korea, Taiwan, or Bangladesh,- with population densities ranging between 517 and 1237 people per square km.

However, we also find two African countries, Burundi and Rwanda, with a high popopulation densities of around 435 to 470 people per square km. This population density is comparable to that of India, which is around 440 people per square km.
Afrika's most populous country, Nigeria, already as a population density of around 200 people per square km - which is very similar to that of Italy with a density of 204 people per square km.

It is also interesting that both Uganda and Malawi have population densities, which are higher than that of China - 195 and 183, as compared to 147.

In 2050, at least 16 African countries will be among the 50 most densely populated places in the world. If we would include the countries from Western Asia the number of densely populated countries on the African continent would be even larger.

In fact, two African countries, Burundi and Rwanda, are projected to be the second and third most densely populated areas in the world (if we exclude the city states of Hong Kong and Singapore). Their population density will be 859 and 1116 people per square km, respectively.

Nigeria, Malawi and Uganda are projected to have population densities of between 438 and 510 people per square km - roughly similar to the Philippines, with a projected population density of 497 people per square km.

It is also interesting to note that Ghana and Benin will have almost identical population densities as Germany - 200 to 220 people per square km.

The enormous population growth in Africa will also result in the situation, that Kenia, Sierra Leone, Burkina Faso, Tanzania, Côte d'Ivoire and Egypt will all have a higher population density than Denmark, China or France.