Germany was taken over by generals. The country was under their control shortly after World War I. Their control was subversive in that they did not announce a coup or rule overtly. They simply took charge and allowed the civilian government to exist.
Corporal Adolf Hitler stayed in the army after the Great War was over. He had no where else to go. He was appointed to a Aufklärungskommando (reconnaisance unit) as an intelligence officer. He was given a mission to infiltrate the German Workers Party (DAP). He accomplished this mission with great flair, ending up as one of the leaders of the party. He became a student of Meister Eckhart and the Thule Society (aryan occultism). The parties name was changed to the National Socialist German Workers Party (NSDAP) and the rest is history.
The question is, at what point (if ever) did Hitler stop working for the Army?
We know he was arrested and sent to prison on the 1st of November 1923 for an attempted coup. He was sentenced to 5 years in April 1924. He was pardoned in December of 1924. During his time he was allowed to send and receive mail and visitors from his “illegal” party.
When he got out he began to rebuild the party and, when the Great Depression started in October of 1929, the NSDAP was able to rise to power on the wave of economic hardship with the promise of a socialist solution to everyone’s problems. In 1933 Hindenburg appointed Hitler as Chancellor. There was a year of terrorist attacks and violence; each one exploited (and probably caused) by the Nazis. By June of 1934 their party was the only legally recognized one in Germany.
He consolidated his control by killing off leaders of his own SA. He stripped a number of generals he didn’t deem to be loyal of their posts. The notable general he did not fire was Friedrich Fromm.
It seems to me Hitler was allowed to take over what was already under the control of a cadre of military officers. He was able to affect the consolidation and control of the military and eliminate any sort of democracy the nation had previously enjoyed. He was part Jewish, which someone out there must have gotten a real kick out of. The real boss would never stand on a podium yelling, gesturing and painting a big target on himself.