On November 8th, 1939, Hitler gave a speech to the Nazi Party's Old Guard at the Beer Hall where he had launched his unsuccessful Putsch sixteen years earlier. He normally spoke from 8.30pm to about 10.00pm so the bomb that was planted by a joiner named George Elser was set to go off at 9.20pm.
Hitler was in full swing, condemning the British, when the bomb planted by Elser detonated. Hitler and his deputy Rudolf Hess were killed instantly.
The German people, shocked by the killing of their beloved Fuhrer, went into mourning. The Soviet leader Josef Stalin and the Italian leader Benito Mussolini offered their condolences. British Prime Minister Neville Chamberlain labelled his death a great victory for freedom in Europe. In both the Protectorate of Bohemia and Moravia and in Poland people danced in the streets until SS troops dispersed them with their usual brutality.
With the Hitler spell being broken a three way power struggle emerged between Goering and the military in one camp; Goebbels, Bormann and the Nazi Party in the second; and Himmler and the SS formed the third camp. To the shock of just about everyone in Germany, Albert Speer was sworn in as the new Fuhrer of the Greater German Reich on November 11th, 1939, mostly because he was the only one that everyone could agree on and because they believed he could be easily manipulated.
Mein Fuhrer Speer proved to be a very astute leader with a reputation for hard work and a ruthless streak. He sacked Himmler as head of the SS and replaced him with Reinhard Heydrich, a decision he would later regret. Himmler was put in charge of the Protectorate of Bohemia and Moravia. Bormann was dismissed and secretly executed because he knew too much. Goering was left in charge of the air force but the economic portfolio was placed under Johannes von Popitz, the Prussian foreign Minister who took over the Economics Ministry. Goebbels retained his role as propaganda minister. Joachim von Ribbentrop was fired as the Foreign Minister.
Speer immediately assured Stalin that he would continue to abide by the Hitler-Stalin Pact signed in August 1939 "until futher notice". He then approached the British Prime Minister Neville Chamberlain to discuss a ceasefire. Chamberlain reasserted that Germany had to withdraw from Poland before any ceasefire would be considered. Speer refused so the war continued.
(In the OTL Hitler cut the Beer Hall speech short and left the hall about ten minutes before the bomb went off. The rest, so they say, is history.)