With the outbreak of World War II in September 1939, the WJC headquarters moved from Paris to Geneva to facilitate communications with Jewish communities in Europe. In the summer of 1940, by which time most of Europe had fallen under Nazi occupation, the World Jewish Congress's headquarters were moved to New York to share office space with the American Jewish Congress, and a special WJC office was set up in London. The British Section of the WJC was tasked with acting as the European representative of the organization.