Following the Night of the Long Knives in 1934, in which the only serious challengers to Hitler's hegemony – Ernst Röhm's brownshirts – were murdered by the SS and Gestapo, Hitler assumed total control of Germany's entire military and all branches of government. Two months later, he led the annual Rally during which thousands of Nazis swore their allegiance.
These rallies were held from 1923 to 1938, but the Rally in 1934 was the first official imperial party congress (the Reichsparteitag) under Hitler, and marked the beginning of the nightmare of Nazism. The Rally was filmed by Leni Riefenstahl as Triumph of the Will. The Rally in 1936 coincided with Germany's remilitarisation of the Rhineland which was celebrated as a reclamation of German honour after the humiliations of the Versailles and Locarno Treaties.
The 1936 Olympic Games were staged in Berlin, and went ahead despite international calls to boycott them. Jesse Owens won four gold medals, brilliantly undermining Hitler's theory of Aryan superiority.
The British Ambassador to Germany attempted to persuade the British press to paint Hitler as "an apostle of Peace", to encourage him to do the right thing, rather than vilify him and risk war.
Chamberlain met with Hitler twice, and after his second meeting in 1938 returned waving the famous piece of paper, saying he had secured peace in our time. He had brokered the Munich Agreement, a pledge between Britain, Italy, France and Germany which gave Hitler carte blanche to annex the Sudetenland, part of Czechoslovakia. The Sudetenland had been taken from Germany after World War One as one of the conditions of the Treaty of Versailles.
Chamberlain's announcement on 3 September 1939 to the United Kingdom: Britain was now at war with Germany (audio).