Africa had seen the development of European colonies during the decades before the First World War, but at the Berlin Conference of 1884 the European powers had agreed that these colonies would remain neutral if war broke out in Europe. That didn’t happen: there were campaigns all over the continent, with the biggest taking place in East Africa. European troops were thin on the ground but they enrolled large native armies, supported by huge numbers of African carriers. European colonials were dismayed by these campaigns, which upset trade and caused local resentment. For those European regiments which fought in Africa the biggest killer was disease. All in all, the African campaigns were a very costly sideshow.