The Germans did commit genocide in Africa, but it was not the Nazis. The German's committed genocide in German Southwest Africa, known today as Namibia. It's generally considered the first genocide of the twentieth century.

It was particularly brutal, and I've always wondered why the Germans acted so maliciously. They drove the Hereros into the desert, intentionally starved them, gunned them down, and poisoned the drinking water. Somewhere around 100,000 people were murdered between 1904-1907.

General von Trotha, the commander in charge of taming the colony, issued this declaration:

I, the great general of the German troops, send this letter to the Herero people... All Hereros must leave this land... Any Herero found within the German borders with or without a gun, with or without cattle, will be shot. I shall no longer receive any women or children; I will drive them back to their people. I will shoot them. This is my decision for the Herero people."

There's a good popular history book called The Kaiser's Holocaust that I've briefly looked read through.