So what actually led up to these terrible events? By examining Hitler himself and his first few years in power, we can get a good impression of the reasons.
Firstly, Hitler had always been an extremist anti-Semitic. It has been well argued that Hitler only wanted to expel all Jews from Germany until 20 January 1942, the date of the Wannsee Conference, when he decided on the “final solution”. This might be true, but it is still also true that Hitler was promoting anti-Semitic attitudes in Germany from the start of his reign. This might be very general point to make, but I can specify an exact occasion of this anti-Semitism.
In September 1935, two years after the Nazis came to power, Hitler implemented the Nuremburg Race Laws. There were three such laws – the first, “The Law for the Protection of German Blood and German Honour” prohibited marriages and extra-marital intercourse between Jews and “Aryans” and also the employment of German females under forty-five in Jewish households.
The second law, “The Reich Citizenship Law” did not allow Jews to have German citizenship, making a distinction between “nationals”(Jews) and “Reich citizens”(Hitler’s “Aryans”).
The third law, known as the “Law for the Protection of Hereditary Health: The Attempt To Improve the German Aryan Breed”, merely stated that anyone suffering from a hereditary (or supposedly hereditary) disease or illness could be sterilised by the state to prevent it spreading down to children.
These laws started a direct policy of anti-Semitism in Nazi Germany.
However, just because these laws had been passed, it did not automatically mean that the public would accept them. Anti-Semitism remained at a fairly low level from 1935 to 1938, until in the latter year; one man, Zindel Grynszpan, and his family were forced over the Polish border by the Nazi regime. Grynszpan’s son heard of his family’s plight and immediately forced his way into the German embassy in France to assassinate the German ambassador. Upon discovering that the Ambassador was not in the embassy, he settled for a lesser official, Third Secretary Ernst vom Rath. The assassination provided Joseph Goebbels, Hitler's Chief of Propaganda, with the excuse he needed to launch an attack against German Jews, thus leading to the event called Kristallnacht.
Cases of violent anti-Semitism became more prominent after this. In 1939, the Nazis invaded Poland. Hitler and other high-ranking Nazi officials began to realise that forcing Jews to emigrate was not a time efficient way of disposing of their hated race, as they had gained even more Jewish people after having conquered a country with a large Jewish population. Goebbels and others began to promote violence against Jews more and more, and with the invasion of the USSR in 1942, Hitler realised that there had to be another way. Germany had to devote more time to fighting the newly started Second World War than disposing of harmless Jews.
So, ultimately in 1942, Hitler organised the Wannsee Conference to decide upon the “final solution”. This basically said that the time had come for industrial extermination of the Jewish race. Concentration camps changed to Death camps, and genocide in Germany had begun.
I believe that Kristallnacht was the most important development in the change of Nazi policies towards Jews because it showed the Nazis that the German public had finally truly acclimatised to an extremist anti-Semitic state. This led to the Nazis being able to justify Death camps and, in a word, the holocaust, to them.