 She settled in New York City where she spent the rest of her life.Radziwiłł played a major role in exposing "The Protocols of the Elders of Zion".In 1921, she gave a private lecture in New York in which she claimed that the "Protocols" were compiled in 1904-1905 by Russian journalists Matvei Golovinski and Manasevich-Manuilov at the direction of Pyotr Rachkovsky, chief of the Okhrana, the Russian secret service in Paris.