A lifetime of activism began a few years later when he joined the Irgun, the armed Jewish underground movement.
In 1937, he went to Poland to help smuggle Jews into Palestine.
Bergson came to the United States in 1940. Two years later, his efforts were almost entirely focused on increasing awareness of the genocide — which to that point had received little if no attention in the U.S. media — through advertisements, rallies and plays.
Bergson co-founded the Emergency Committee to Save the Jews in Europe in 1943. His causes piqued the interest of eminent actors such as Edward G. Robinson, Marlon Brando and Stella Adler, who toured the United States performing in the plays and appearing at the rallies.
Some credit Bergson’s work for impelling the U.S. government’s decision to create the War Refugee Board in 1944, the first federal organization to deal with the perilous position of European Jews.
“He was a master of public relations at a very young age,” his daughter, Rebecca Kook, a political science professor at Ben-Gurion University in Israel, told the New York Times. “In many ways, he established what many consider to be the first example of a real political lobby in Washington.”
After considerable success in the United States, Bergson returned to Palestine in 1948 and reverted to his birth name, which he had changed in order to shield his family from his political activism.
He was elected to the nascent state’s assembly as a member of Menachem Begin’s Herut Party when Israel declared independence.
Bergson is survived by Nili Haskell, whom he married in 1975, two daughters and three grandchildren.