Kony?

Kony is actually a very bad comparison, since Uganda wasn't in full fledged civil war, and he was more of a fringe character that was blown up by the western media.

This is loosely based on a number of civil wars in west africa, particularly Sierra Leone and Liberia, and Cote D'Ivore.

A better comparison would be to General Buttnaked in Liberia, who was a deeply superstitious shaman warlord who used child soldiers in a war that closely resembles the setting Beasts of no nation. Him and his troops would run into battle naked, and he convinced his soldiers they were immune from bullets (something Elba's character also did).

But there are countless warlords in the mold of Idris Elba's character across many civil wars in Africa, both east and west. And i'm sure its not just Africa, these characters existed in central and latin american wars in the 80's, in asia,...human condition i guess.