Rudolf Walter Ladenburg was a German atomic physicist. He emigrated from Germany as early as 1932 and became a Brackett Research Professor at Princeton University. When the wave of German emigration began in 1933, he was the principal coordinator for job placement of exiled physicists in the United States. Albert Einstein gave the eulogy at Rudolf's funeral. He and his wife Elsa had three children, Margarethe, Kurt, and Eva. Kurt had two children, Toni and Nils Ladenburg.