On 1 April 1933, the recently elected Nazis organized a one-day boycott of all Jewish-owned businesses in Germany.
The department store Einstein was one of the Jewish businesses in Laupheim picketed by local members of the SA.
Whilst hiking in the mountains in August 1933, Einstein's twenty-year-old sister Clärle was killed by lightning in front of his eyes.
During antisemitic actions in Laupheim in 1934, Siegfried Einstein was chased across the school yard and injured by being pelted with stones[1] whereupon, on 26 September 1934, he fled to Switzerland and settled in the municipality of Au in the Canton of St. Gallen.
Einstein's father was subsequently released from the concentration camp, physically and mentally a broken man.
Between 24 February 1941 and 25 June 1945, Siegfried Einstein, being a stateless foreigner, was interned by the Swiss government in nine labour camps and forced to work in road construction, draining swamps and as a clerical assistant.
[4] In 1962 he travelled to Moscow, where he met Ilya Ehrenburg, Konstantin Fedin, Yevgenia Ginzburg and Lev Kopelev.
He died suddenly of a heart attack in Mannheim and was buried next to his sister, Clärle, in the Jewish cemetery in Laupheim.