Between 1933 and 1945, Germany’s Nazi government under Adolf Hitler attempted to rid German territory of people who did not fit its vision of a “master Aryan race.” Grune and other homosexuals in Germany felt the impact of the new regime within weeks of Adolf Hitler’s appointment as chancellor in January 1933.
In February, police and Storm Troopers began enforcing orders to shut same–sex bars and clubs. During a crackdown over the next several months, most gathering places for homosexual men and women were closed down, fundamentally disrupting their public lives. Grune was arrested in December 1934, one of 70 men caught in a wave of related denunciations.
Under interrogation, Grune admitted to being homosexual. He was held in “protective custody” for five months, then returned to his childhood home on the German–Danish border to stand trial for violating Paragraph 175. In September 1936, Grune was convicted and sentenced to prison for one year and three months, minus time already served in protective custody. It is estimated that some 50,000 men served prison terms as convicted homosexuals.
At his release, the Gestapo returned Grune to protective custody, asserting that the sentence had been too lenient. In early October 1937, Grune was sent to the Sachsenhausen concentration camp, where he remained until being transferred to the Flossenbürg camp in early April 1940.
World War II helped to conceal the Nazis’ radicalized persecution at home. Thousands of homosexuals were sent to forced labor camps. There, in an explicit campaign of "extermination through work," homosexuals and other so-called security suspects were assigned to gruelling work in ceaselessly dangerous conditions.
Grune himself remained in the Flossenbürg camp until 1945. As American forces approached, he escaped the evacuation of Flossenbürg and joined his sister in Kiel. He spent much of the rest of his life in Spain, but later returned to Kiel, where he died in 1983.