Régime change in January 1933 was followed by a Nazi paramilitary invasion of parliament in March 1933, during the course of which communist members were arrested. Democratic processes were being systematically abolished and the final sitting of the parliament took place in June 1933. Marie Henning was arrested several times during the twelve Nazi years, although sources are vague as to times and places. She appears to have been arrested between May and June 1933 and again in March 1936. Her final arrest came in the context of "Aktion Gitter", a mass arrest of more than 5,000 people that took place overnight on 22/23 August, probably in response to an assassination attempt against the leader on 20 July 1944. Those arrested were identified on (in many cases out of date) lists of people who had been politically active members of (non-Nazi) political parties before 1933. Marie Henning was one of those who were released in September 1944 after just a few weeks in detention.