Obedience to authority

The Stanley Milgram Experiment was created to explain some of the concentration camp horrors of the World War 2, where Jews, Gypsies, homosexuals, Slavs and other enemies of the state were slaughtered by Nazis.

  Do as you’re told

Many war-criminals claimed they were merely following orders and could not be held responsible for their actions, in the trials following the World War 2.
 Were the Germans in fact evil and cold-hearted, or is this a group phenomenon which could happen to anyone, given the right conditions?

For further information:

Simply Psychology.
Explorable

Unbelievable, isn't it?