The Nazi regime in Germany from 1933 to 1945 waged a veritable war throughout Europe to eliminate neurologic disease from the gene pool. Fueled by eugenic policies on racial hygiene, the Nazis first undertook a sterilization campaign against “mental defectives,” which included neurologic patients with epilepsy and other disorders, as well as psychiatric patients. From 1939-41 the Nazis instead resorted to ”euthanasia” of many of the same patients. Some neuroscientists were collaborators in this program, using patients for research, or using extracted brains following their murder. Other reviews have focused on Hallervorden, Spatz, Schaltenbrand, Scherer, and Gross, but in this review the focus is on neuroscientists not well described in the neurology literature, including Scholz, Ostertag, Schneider, Nachtsheim, and von Weizsäcker. Only by understanding the actions of neuroscientists during this dark period can we learn from the slippery slope down which they traveled, and prevent history from repeating itself.