 A small international conference was held in 1904, leading to the first world congress in August 1905 in Boulogne-sur-Mer, France.There were 688 Esperanto speakers present from 20 nationalities.At this congress, Zamenhof officially resigned his leadership of the Esperanto movement, as he did not want personal prejudice against himself (or anti-Semitism) to hinder the progress of the language.