Part 12/17:
By the 1930s, Kats and Ellen Bogan's relationship with the Nazi regime came into focus. Living in Germany during the rise of the Nazis, despite his Catholicism, he was defined as Jewish by Nazi racial law. He fled to Czechoslovakia, then France, but was detained by the Gestapo during WWII. Despite the suspicion cast on him due to his Jewish ancestry, Kats and Ellen Bogan continued collaborating with Nazi forces—examining prisoners, facilitating medical experiments, and participating in eugenic geneology research aimed at exempting certain prisoners from extermination.