In April 1939, when the Nazis were arresting Jews in Berlin, seven-year-old Mikhail and his three-year-old brother Robert were sent alone to the United States to join their father, who had fled months earlier. His mother joined the family by escaping through Italy in 1940. The family moved to New York City on April 28, 1939. His father, whose original name was Pavel Nikolaevich Peschkowsky, changed his name to Paul Nichols, Nichols derived from his Russian patronymic. Before Paul Nichols had received his U.S. medical license, he was employed by a union on 42nd Street, X-raying union members. He later had a successful medical practice in Manhattan, enabling the family to live near Central Park.