On 10 May 1932 Kaiser was one of a number of intellectuals showing public solidarity with the anti-war anti-Fascist campaigner Carl von Ossietzky, attempting to accompany the condemned man all the way to the prison door after the failure of his appeal hearing.
[2] In January 1933 the NSDAP (Nazi Party) took power in Germany and early in 1934 the Vossische Zeitung was closed down which left Bruno Kaiser without a job.
In 1946, shortly after the war, with the help of Kaiser's work on inventorizing the archive, the municipality was able to open the Liestal Poets and Town Museum, its ground floor devoted to the Herweghs and their literary output.
[4] In 1943 Kaiser also joined the Swiss branch of the (increasingly Soviet sponsored) Free Germany Movement (BFD / Bewegung Freies Deutschland).
[1] In the summer of 1947, after a period in Belgium, Bruno Kaiser, with his wife Stascha, returned to Berlin which by now was in the Soviet occupation zone (SBZ / Sowjetische Besatzungszone) of what remained of Germany.
His own book collection, acquired during his youth and subsequent exile, already made him one of the most important bibliophile/book collectors in what was becoming the German Democratic Republic (formally founded in 1949 from what till then had been the SBZ).
Kaiser was put in charge of creating and managing the Berlin institute, which now became his life's work, and a responsibility that closely matched his interest, abilities and experience.
[2] Building the library from nothing, and with necessarily restricted funding, involved a large amount of book collecting, for which he had already demonstrated his talents, and Kaiser also undertook extensive international networking with institutional heads in other countries.