Final answer:
Rosenberg's Bagels was named after Ethel and Julius Rosenberg, who were involved in a notorious espionage case during the Cold War.
Step-by-step explanation:
Rosenberg's Bagels was named after Ethel and Julius Rosenberg, an American couple of Jewish origins. The Rosenbergs became infamous for their role in a cold war espionage case where they were accused of passing on atomic secrets to the Soviet Union. This accusation was primarily due to Ethel's brother, David Greenglass, who, under interrogation, implicated the couple after he was named by Harry Gold, the middleman for Klaus Fuchs, a British physicist who had confessed to espionage. In 1950, the Rosenbergs were arrested, and their subsequent execution divided American public opinion.