The greatest challenge to Hitler's survival during the early years of the Third Reich came from his own brown-shirted storm troopers, the SA (Sturmabteilung) led by Chief of Staff, Ernst Röhm.
The battle-scarred Röhm was a decorated World War I combat officer and a post-war street-brawler who had been with Hitler from the start. Röhm's jack-booted storm troopers were largely responsible for putting Hitler in power. On the front lines of the Nazi political revolution, they had risked their necks battling Communists for control of the streets and squashed anyone who stood in Hitler's way.
However, by the beginning of 1934, a full year after Hitler's seizure of power, things had changed. The SA's usefulness as a violent revolutionary force had effectively ended. To maintain his position as dictator of Germany, Hitler now needed the support of the all-powerful German General Staff with its 100,000-strong Army which had the power to crush his dictatorship whenever it pleased.
The big problem for Hitler was that Röhm and his arrogant young Brownshirts fancied themselves as the nucleus of new "people's army" that would replace the traditional Germany Army – similar to Napoleon's revolutionary army.