The conference was mainly noted for the confrontation between the Proudhonistmutualists and the collectivist position, defended by Marx's envoy for the General Council and Bakunin both. But the Belgian socialist de Paepe played a decisive role in bringing the Belgian delegation across to the collectivist side and isolating the mainly French Proudhonists.
Seventy-five delegates assembled: from Great Britain, the 6 members of the General Council, Applegarth, Eccarius, Cowell Stepney, Lessner, Lucraft, and Jung; from France, which sent 26 delegates, among whom we may mention Dereure, Landrin, Chémalé, Murat, Aubry, Tolain, A. Richard, Palix, Varlin, and Bakunin: Belgium sent 5 delegates, among whom were Hins, Brismée, and De Paepe; Austria 2 delegates, Neumayer and Oberwinder; Germany sent 10 delegates, among whom were Becker, Liebknecht (Member of Parliament), Rittinghausen, Spier (Party chairman) and Hess; Switzerland had 22 representatives, among whom were Burkly, Greulich, Fritz Robert, Guillaume, Schwitzguébel, and Perret; Italy sent but one delegate, Caporusso; from Spain there came Farga-Pellicer and Sentinon; and the United States of America was represented by Cameron. Jung was elected chairman of the congress.