Raoul Wallenberg    http://www.ushmm.org/wlc/en/article.php?ModuleId=10005211

Wallenberg studied in the United States of America (WRB)  in the 1930's and had established himself in a business career in Sweden. Wallenberg was recruited by the US War Refugee Boarding in June 1944 to travel to Hungary. His objective was to see what he can do to save Hungarian Jews. 

He was given the job as first secretary to the Swedish legation in Hungary, Wallenberg arrived in Budapest on July 9, 1944. Despite a complete lack of practice in diplomacy and clandestine operations, he led one of the most extensive and successful rescue efforts during the holocaust (mass murder of 6 million Jews). His work with the WRB and the World Jewish Congress prevented the deportation of tens of thousands of Hungarian Jews to the Auschwitz-Birkenau killing center.

By July 1944, the Hungarians and the Germans had deported nearly 440,000 Jews from Hungary, almost all of them to Auschwitz-Birkenau, where the SS killed approximately 320,000 of them upon arrival and forced the rest into labor at Auschwitz and other camps. Nearly 200,000 Jews remained in Budapest. The Hungarian authorities intended to deport them as well in compliance with German requests.

With authorization from the Swedish government, Wallenberg began distributing certificates of protection issued by the Swedish legation to Jews in Budapest He used WRB and Swedish funds to establish hospitals, nurseries and a soup kitchen, and to designate more than 30 “safe” houses that together formed the core of the "international ghetto" in Budapest. The international ghetto was reserved for Jews and their families holding certificates of protection from a neutral country.