Perhaps fearing that Von Trotha would turn on them after defeating the Ovaherero, the Witbooi and other Nama groups joined the rebellion.  This led to the end of Leutwein's native policy and his eventual replacement as Landeshauptmann in 1905. Von Trotha went on to lead a military campaign of genocide, relentlessly pursuing the Ovaherero into the desert where many died of thirst and starvation.  Out of a population of 60,000 to 80,000 Ovaherero in South West Africa before the war only 15,130 remained by 1911 and of the 20,000 Nama only 9,781.