I remember as a kid watching a TV documentary on experiments in which people were told to inflict pain on others with electric shock (and the people being shocked would cry out). But people followed orders without complaint.
Those were Milgram's experiments, aren't they?
He conducted his experiment at Yale in the early 1960s. The arrest (and subsequent trial) of Adolf Eichmann had brought the Holocaust back to the front pages and he was curious about whether Americans (or any group of people) were capable of building a comparable infrastructure and carrying out a mass murder on the scale the Nazis had done some twenty years prior.
When later asked if he thought he could find a sufficient number of Americans in this country who could do such a thing, he reportedly replied that he thought he could find enough people for the job in New Haven (CT).