Prussian Cultural Heritage Foundation possesses thousands of African skulls. ARD identified 1,000 from Rwanda and 60 from Tanzania. Skulls collected in German East Africa colony from 1885 to World War I. Many from insurgents killed by German troops. Collectors hoarded remains for scientific racism studies. Eugenics scientists used skulls to develop racial superiority theories. Human zoos displayed live Africans as caged animals. Bounty hunters killed or exhumed Africans to sell skulls to Europeans. Nazi experiments traced roots to this colonial scholarship. Germany recently repatriated remains to Namibia, Australia, Paraguay. Spain returned stuffed Kalahari man to Botswana in 2000. France returned 20 Maori heads to New Zealand in 2012. Chicago's Field Museum returned Tasmanian Aboriginal remains. London returned 138 Torres Strait Islander skeletons. New York returned 180 Onondaga Nation remains. Rwanda demands swift return of its skulls. Tanzanians express outrage over ancestral desecration.