This map, created by British cartographer John George Bartholomew and published in 1899 as part of Harry Hamilton Johnston's book A History of the Colonisation of Africa by Foreign Races (A history of the colonisation of Africa by foreign races).

The book was created in the context of the struggle between European colonial powers to divide up Africa. This particular map shows the complexity of accessing and successfully colonising different parts of Africa. It uses the following colour coding for this purpose:

• Rosa: A healthy and colonisable Africa, where Europeans can eventually become the predominant race, where essentially European states can be formed.
• YellowAfrica is fairly healthy, but where unfavourable soil conditions, water supply or the previous establishment of warlike or enlightened native races or other causes may prevent European colonisation.
• Light greyUnhealthy but exploitable Africa. Impossible for European colonisation, but largely commercially valuable and inhabited by fairly docile and governable races. The Africa of the trader and of despotic European control.
• Dark grey: Africa is extremely unhealthy.

Sources

• Colonizability of Africa
• A history of the colonisation of Africa by alien races (PDF)