Just two decades after World War I, the deadliest and most widespread war of all time broke out. It became known as World War II. World War II began when Germany invaded Poland in 1939. The Nazis played an important role in this war of monumental proportions (World War II). Adolf Hitler was the mastermind behind the Nazis' plans (Adolf Hitler). The Nazis established efficient mass murder killing centers (Killing Centers: An Overview). Unlike concentration camps, which served as labor and detention centers, extermination centers were used only to kill non-Aryan individuals. He organized, implemented and executed the terror that the Nazis brought upon millions of innocent human beings. He was behind the systematic extermination and ethnic cleansing of six million Jews and millions of non-Aryans, such as gypsies and Jehovah's Witnesses (Adolf Hitler). Say no to plagiarism. Get a tailor-made essay on "Why Violent Video Games Shouldn't Be Banned"? Get an original essay It is estimated that the Nazis killed five to seven million innocent Jews during the period of World War II (The Holocaust: An Introductory History). The Nazis killed Jews in many different ways. They killed them mainly in the gas chambers and by shooting. Overwork, starvation, and disease also killed some non-Aryans (Methods of Murder). There were gas chambers in almost all Nazi camps, including concentration camps. In the gas chambers people usually died within a few minutes from lack of oxygen. While under guard, the prisoners were forced to carry the corpses. These prisoners, known as sonderkommandos, were ordered to remove all valuables from the corpses. The bodies were buried in mass graves or burned in ovens. One of the most evil things the Nazis did was how they tricked the Jews into entering the chambers. The guards told them they were going to take a shower to get rid of the lice, but then the guards closed and locked the doors and threw Zyklon-B pellets into the rooms (Bachrack 52). The chemicals mainly used in the chambers were carbon monoxide and Zyklon-B (poisonous gas). Healthier Jews who were not selected for early death were put to hard work as sonderkommandos and other tedious jobs. Over 1 million Jews were shot by SS commandos. These commandos followed the troops as they invaded different places, and then rounded up all the Jews, shot them, and then threw the bodies into the ditches (Methods of Murder). Another way the Nazis used to exterminate the “undesirables” was gas trucks. The Jews were forced into trucks which were hermetically sealed, and then the exhaust fumes from the truck were transported to the area full of Jews, who suffocated quite quickly (Methods of Mass Murder). The Nazis were relentless in their attempt to make the Aryan race the dominant species. Approximately seven million people were massacred as a result of the Nazi extermination processes. The sole goal of Hitler's regime was to exterminate non-Aryans (victims). Even in Germany there were people who did not agree with Nazi policies, and some were even willing to die for their beliefs. One of these groups were Jehovah's Witnesses. Hitler felt very threatened by them because, from the beginning, Jehovah's Witnesses remained steadfast in their beliefs and would recognize only one God (The Holocaust: Non-Jewish Victims). Similar to Jews and Jehovah's Witnesses, Gypsies were senselessly murdered by the Nazis. Gypsies were known to be a nomadic group and.