In the USA, as in Britain, the great wave of Jewish immigration from Eastern Europe began in the 1880s and continued at a high level until it was interrupted by the First World War. The intellectual and political leadership of the New York Jewish immigrant community, relatively well educated and relatively urbanised, was modern in outlook from the moment of disembarkation at Ellis Island or Castle Garden. The ranks of Jewish socialists in New York were also swelled by Mensheviks and other dissidents expelled from the Soviet Union in the 1920s and by victims of anti-Jewish outbreaks in Poland. Later there was a steady stream of refugees from Nazism. The newcomers sustained links with comrades in Europe, and with other émigré communities from Prague and Paris to North Africa and Shanghai. The Jewish Labor Committee and its constituent unions were attuned to reports of persecution and in close touch with exiles, both Jewish and non-Jewish, in their places of refuge.