The so-called Second International (1889–1914) was formed as the successor organization to the International Working Men's Association and was administered from a central office in Brussels.
Camille Huysmans (1871–1968) in the office of the secretariat of the Socialist International in Brussels, ca. 1915, black-and-white photograph, photographer unknown; source: with kind permission © Archives of Social Democracy, Friedrich-Ebert-Stiftung Bonn, signature 6/FOTA064276, https://www.fes.de/archiv-der-sozialen-demokratie.