Wars between herders and farmers

 There are serious armed conflicts between nomadic herders and settled farmers in 

Cameroon

Central African Republic

Congo

Kenya, and 

Sudan (where clashes have been exacerbated by the ongoing civil war)

Herder/farmer conflicts have a long history, going back to the story of Cain and Abel in the book of Genesis in the bible. Man-made climate change is bringing added pressure on usable land, and population growth and improvements in the treatment of tetse fly and other cattle diseases are other factors.

This issue is challenged by some researchers, who believe that the herder-farmer conflict diagnosis has been used to cover other problems. https://www.iied.org/10208iied

The solution here is for authorities to arrange for agreed migration routes for herders to move their cattle to market. The UN could find a role here in spreading word and assisting with negotiations.

More on this here: https://www.iied.org/mitigating-farmer-herder-conflict