A week later, the workers' rebellion of 17 June 1953 pushed those debates from the agenda. Eisler fell into a depressive mood, and did not write the music for the opera. In his last work, "Ernste Gesänge" (Serious Songs), written between spring 1961 and August 1962, Eisler attempted to work through his depression, taking up the 20th Congress of the Communist Party of the Soviet Union with its demise of the Stalin cult, as a sign of hope for a future enabling to "live without fear". Although he continued to work as a composer and to teach at the East Berlin conservatory, the gap between Eisler and the cultural functionaries of East Germany grew wider in the last decade of his life. During this period, he befriended musician Wolf Biermann and tried to promote him (but in 1976, Biermann would be stripped of his GDR citizenship while on concert tour in West Germany).