Here's what Wikipedia has to say about Richard Strauss:

Strauss in Nazi Germany
Reichsmusikkammer
In March 1933, when Strauss was 68, Adolf Hitler and the Nazi Party rose to power. Strauss never joined the Nazi party, and studiously avoided Nazi forms of greeting. For reasons of expediency, however, he was initially drawn into cooperating with the early Nazi regime in the hope that Hitler—an ardent Wagnerian and music lover who had admired Strauss' work since viewing Salome in 1907—would promote German art and culture. Strauss's need to protect his Jewish daughter-in-law and Jewish grandchildren also motivated his behavior,[18] in addition to his determination to preserve and conduct the music of banned composers such as Gustav Mahler and Claude Debussy.

In 1933, Strauss wrote in his private notebook:

I consider the Streicher-Goebbels Jew-baiting as a disgrace to German honour, as evidence of incompetence—the basest weapon of untalented, lazy mediocrity against a higher intelligence and greater talent.
Meanwhile, far from being an admirer of Strauss's work, Joseph Goebbels maintained expedient cordiality with Strauss only for a period. Goebbels wrote in his diary:

Unfortunately we still need him, but one day we shall have our own music and then we shall have no further need of this decadent neurotic.

Nevertheless, because of Strauss's international eminence, in November 1933 he was appointed to the post of president of the newly founded Reichsmusikkammer, the Reich Music Chamber. Strauss, who had lived through numerous political regimes and had no interest in politics, decided to accept the position but to remain apolitical, a decision which would eventually become untenable. He wrote to his family, "I made music under the Kaiser, and under Ebert. I'll survive under this one as well." In 1935 he wrote in his journal:

In November 1933, the minister Goebbels nominated me president of the Reichsmusikkammer without obtaining my prior agreement. I was not consulted. I accepted this honorary office because I hoped that I would be able to do some good and prevent worse misfortunes, if from now onwards German musical life were going to be, as it was said, "reorganized" by amateurs and ignorant place-seekers.
Strauss privately scorned Goebbels and called him "a pipsqueak". However, in 1933 he dedicated an orchestral song, "Das Bächlein" ("The Little Brook"), to Goebbels, in order to gain his cooperation in extending German music copyright laws from 30 years to 50 years.

Strauss attempted to ignore Nazi bans on performances of works by Debussy, Mahler, and Mendelssohn. He also continued to work on a comic opera, Die schweigsame Frau, with his Jewish friend and librettist Stefan Zweig. When the opera was premiered in Dresden in 1935, Strauss insisted that Zweig's name appear on the theatrical billing, much to the ire of the Nazi regime. Hitler and Goebbels avoided attending the opera, and it was halted after three performances and subsequently banned by the Third Reich.

On 17 June 1935, Strauss wrote a letter to Stefan Zweig, in which he stated:

Do you believe I am ever, in any of my actions, guided by the thought that I am 'German'? Do you suppose Mozart was consciously 'Aryan' when he composed? I recognise only two types of people: those who have talent and those who have none.
This letter to Zweig was intercepted by the Gestapo and sent to Hitler. Strauss was subsequently dismissed from his post as Reichsmusikkammer president in 1935. The 1936 Berlin Summer Olympics nevertheless used Strauss's Olympische Hymne, which he had composed in 1934. Strauss's seeming relationship with the Nazis in the 1930s attracted criticism from some noted musicians, including Arturo Toscanini, who in 1933 had said, "To Strauss the composer I take off my hat; to Strauss the man I put it back on again", when Strauss had accepted the presidency of the Reichsmusikkammer. Much of Strauss's motivation in his conduct during the Third Reich was, however, to protect his Jewish daughter-in-law Alice and his Jewish grandchildren from persecution. Both of his grandsons were bullied at school, but Strauss used his considerable influence to prevent the boys or their mother being sent to concentration camps.

Friedenstag
In 1938, when the entire nation was preparing for war, Strauss created Friedenstag (Peace Day), a one-act opera set in a besieged fortress during the Thirty Years' War. The work is essentially a hymn to peace and a thinly veiled criticism of the Third Reich. With its contrasts between freedom and enslavement, war and peace, light and dark, this work has a close affinity with Beethoven's Fidelio. Productions of the opera ceased shortly after the outbreak of war in 1939.


Strauss at Garmisch in 1938
When his Jewish daughter-in-law Alice was placed under house arrest in Garmisch-Partenkirchen in 1938, Strauss used his connections in Berlin, including opera-house General Intendant Heinz Tietjen, to secure her safety. He drove to the Theresienstadt concentration camp in order to argue, albeit unsuccessfully, for the release of Alice's grandmother, Paula Neumann. In the end, Neumann and 25 other relatives were murdered in the camps. While Alice's mother, Marie von Grab, was safe in Lucerne, Switzerland, Strauss also wrote several letters to the SS pleading for the release of her children who were also held in camps; his letters were ignored.

In 1942, Strauss moved with his family back to Vienna, where Alice and her children could be protected by Baldur von Schirach, the Gauleiter of Vienna. However, Strauss was unable to protect his Jewish relatives completely; in early 1944, while Strauss was away, Alice and his son Franz were abducted by the Gestapo and imprisoned for two nights. Strauss's personal intervention at this point saved them, and he was able to take them back to Garmisch, where the two remained under house arrest until the end of the war.

Metamorphosen
Strauss completed the composition of Metamorphosen, a work for 23 solo strings, in 1945. The title and inspiration for the work comes from a profoundly self-examining poem by Goethe, which Strauss had considered setting as a choral work. Generally regarded as one of the masterpieces of the string repertoire, Metamorphosen contains Strauss's most sustained outpouring of tragic emotion. Conceived and written during the blackest days of World War II, the piece expresses Strauss's mourning of, among other things, the destruction of German culture—including the bombing of every great opera house in the nation. At the end of the war, Strauss wrote in his private diary:

The most terrible period of human history is at an end, the twelve year reign of bestiality, ignorance and anti-culture under the greatest criminals, during which Germany's 2000 years of cultural evolution met its doom.
In April 1945, Strauss was apprehended by American soldiers at his Garmisch estate. As he descended the staircase he announced to Lieutenant Milton Weiss of the U.S. Army, "I am Richard Strauss, the composer of Rosenkavalier and Salome." Lt. Weiss, who was also a musician, nodded in recognition. An "Off Limits" sign was subsequently placed on the lawn to protect Strauss. The American oboist John de Lancie, who knew Strauss's orchestral writing for oboe thoroughly, was in the army unit, and asked Strauss to compose an oboe concerto. Initially dismissive of the idea, Strauss completed this late work, his Oboe Concerto, before the end of the year.