Have you noticed how many countries in Africa have the same Red, Yellow and Green Stripes as their national flag? Check the list
I could count:
Sao Tome and Principe
Incidently as per my friend from Senegal al these countries have totally different history, culture and even religion. Many of them are sworn enemies for centuries now. Yet to a layman all their flags looks so much the same.
As my friend Gregory pointed out, this probably has to do with Ethopia (which was the only independent country in the African world)