The Germans were latecomers and bit players in the colonization game. But they did act like Germans.
Darwin had little to do with it. One of the most horrific wars in history was fought in Germany, well before Darwin - the Thirty Years War. Some areas did not recover to their pre-war population until the 19th Century.
I’ve got a nice coin dated 1912, from “Deustche Ostafrika”; I think that became Tanzania.