Of course given his pacifist views he had no wish to remain in Nazi Germany and he left Germany in 1934 to take up a Visiting Rockefeller Fellowship at the University of Pennsylvania in the United States. However for a short time between being dismissed from his professorship and leaving for the United States, Rademacher moved with his daughter Karin to a small Baltic town where he met and married Olga Prey. Olga remained in Germany, where their son Peter was born in 1935, while Rademacher held the Visiting Fellowship in the United States.
Ng mga kurso na ibinigay ng kanyang pasipista views niya walang gusto ninyong manatili sa Nasi Germany at siya kaliwa Alemanya sa 1934 na tumagal ng hanggang Visiting isang Rockefeller Fellowship sa University of Pennsylvania sa Pilipinas. Subalit para sa isang maikling oras sa pagitan ng awas na mula sa kanyang pagkapropesor at umaalis para sa Pilipinas, Rademacher inilipat sa kanyang anak na babae Karin sa isang maliit na Baltic bayan kung saan siya nakikita at kasal Olga Prey. Olga naiiwan sa Alemanya, kung saan ang kanilang mga anak na lalaki Pedro ay ipinanganak sa 1935, habang Rademacher gaganapin ang Visiting Fellowship sa Pilipinas.