Ultimately, when a politician cannot get a person to agree with him by persuasion, he must silence him. Normally this will be by buying his acquiescence in one way or another; as a dictator, you can imprison the man or you can kill him.
By January 1934 Roehm, the head of the SA, was beyond Hitler's control. The SA by now consisted of over 2 million men, all dressed in the familiar brown uniform with jackboots and a round peaked hat. They went everywhere with impunity and, in their local areas, created the terror needed by the totalitarian state. However, while Hitler was beholden to them, he could not have a threat to his supreme rule nor the threat they presented to the complete Nazification of Germany, and his plans for war. Roehm kept on insisting that his men take over from the Army, literally to become the Army. Despite his astuteness and abilities as an organizer, he could not see what was quite obvious to others, that the SA were mainly a collection of thugs and unemployables only good for crowd control and similar police duties. The Army generals were appalled at the idea and Hitler decided that he must have secret talks with them, about both the SA and the presidency.
Hindenburg was fast aging and Hitler had heard that he would soon die. Hitler had no intention that anyone other than himself should be President and so, at the talks with the Army in April, he put this to the generals. In return for their support, he promised to suppress Roehm and the SA; there were also hints that the armed forces would be greatly expanded. All the senior generals agreed with this arrangement and Hitler set in motion the steps leading to the Purge of 30th June 1934.
Goering and Himmler saw this as an opportunity not only to get rid of Roehm , but also to settle some old scores and eliminate some awkward people from both right and left. They drew up long lists of those to be killed but needed to persuade Hitler that there was indeed a very real danger to the Nazi government.
Like the Reichstag fire, the records are not available of the actual course of events, and any accounts there are, are from those directly involved and cannot be trusted. However it is true that Hitler did have a long meeting with Roehm, that Roehm went on leave on 7th June with most of the SA leadership, and that the SA were ordered not to wear uniforms or hold meetings during the month of July. Hitler also went to Venice on 14th June, to hold talks with Mussolini. These known facts do not, therefore gibe with the 'official' explanations, made later, of long-laid plans and a putsch. In addition to these events Papen, who was still Vice-Chancellor, made a speech on 17th June calling for an end to the Nazi excesses and a return to proper government. Despite the agreement with the Army, Hitler knew that there were those who agreed with Papen and were only waiting for Hindenburg to die to try to push through a return of the Hohenzollerns. He had to act soon. The Army also indirectly pushed Hitler by confining all troops to barracks on full alert; expelling Roehm from the Officers' League; and by publishing an article by General Blomberg, the Minister of Defence, supporting Hitler, presumably in whatever actions he decided upon!
