During World War II, Nazi Germany, led by Adolf Hitler, decided to exterminate (kill all of) the Jewish people in Europe. They called this plan the "Final Solution". The Nazis also sent many other people to concentration camps and extermination camps (death camps). As Commandant (commander) at Auschwitz, Höss tested and started using different ways of killing these people more quickly. He started using Zyklon B, a pesticide with hydrogen cyanide in it, to kill prisoners in gas chambers. This allowed Nazi soldiers at Auschwitz to murder 2,000 people every hour. At Auschwitz, he created the largest place meant for the constant mass murder of human beings ever known in history.