What group of people outside of the United States in the 1920s and 1930s carefully studied the American eugenicist movement?

The group of people outside of the United States in the 1920s and 1930s that carefully studied the American eugenicist movement are the Nàzis.

This is because during this period the Nazis supported various programs on eugenics such as the California eugenics operation, and the one's conducted by the likes of Josef Mengele in Auschwitz.

Also, the Nazis from Germany gave Eugenics researcher Harry H. Laughlin an award to show support of the study of movement.

Hence, in this case, the correct answer is "The group of people outside of the United States in the 1920s and 1930s that carefully studied the American eugenicist movement are the Nàzis."

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although the legal justifications for the trials and their procedural innovations were controversial at the time, the nuremberg trials are now regarded as a milestone toward the establishment of a permanent international court, and an important precedent for dealing with later instances of genocide and other crimes

christopher columbus (1492–1504)