While working in the Renault factories, he became acquainted with Bolshevism, and in 1915 left France for Zurich, where he met and befriended Vladimir Lenin, the future leader of the October Revolution of 1917.
While working in the Renault factories, Goldstein became acquainted with Bolshevism. Thus, in 1915 he left France for Zurich, Switzerland, where he met and befriended Vladimir Lenin, the future leader of the October Revolution of 1917.