Maded this map. Well, added the country names and the population numbers. I could have picked another map maybe, but I liked the fact it shows the major rivers.
First I started with Wikipedia, but they changed the article in the meantime, so I decided I rather use this:
https://www.worldometers.info/population/countries-in-africa-by-population/
Additional information:
- where it was over 900 thousand I rounded up to million;
- the red line is the approximate border between the two Sudans, the south one is the freshest country.

What really surprised me was some of the contrast. Like between Algeria and Libya. In their case I'd assume the coastal region is inhabited, while the inner deserty parts are sparsely. Are their coasts so different? What made Algeria so populous? Libyan people don't have sex?