By: History.com Editors

1951

The espionage trial of Ethel and Julius Rosenberg begins

Published: November 13, 2009

Last Updated: January 24, 2025

The trial of Ethel and Julius Rosenberg begins in New York Southern District federal court. Judge Irving R. Kaufman presides over the espionage prosecution of the couple accused of selling nuclear secrets to the Russians (treason could not be charged because the United States was not at war with the Soviet Union). The Rosenbergs, and co-defendant Morton Sobell, were defended by the father and son team of Emanuel and Alexander Bloch. The prosecution includes Roy Cohn, best known for his association with Senator Joseph McCarthy.

David Greenglass was a machinist at Los Alamos, where America developed the atomic bomb. Julius Rosenberg, his brother-in-law, was a member of the American Communist Party and was fired from his government job during the Red Scare. According to Greenglass, Rosenberg asked him to pass highly confidential instructions on making atomic weapons to the Soviet Union. These materials were transferred to the Russians by Harry Gold, an acquaintance of Greenglass. The Soviets exploded their first atomic bomb (and effectively started the Cold War) in September 1949 based on information, including that from Greenglass, they had obtained from spies.

The only direct evidence of the Rosenberg’s involvement was the confession of Greenglass. The left-wing community believed that the Rosenbergs were prosecuted because of their membership in the Communist Party. Their case became the cause célèbre of leftists throughout the nation.

The trial lasted nearly a month, finally ending on April 4 with convictions for all the defendants. The Rosenbergs were sentenced to death row on April 6. Sobell received a thirty-year sentence. Greenglass got fifteen years for his cooperation. Reportedly, the Rosenbergs were offered a deal in which their death sentences would be commuted in return for an admission of their guilt. They refused and were executed.

In 2008, the only surviving defendant, Morton Sobell, admitted that he was a Soviet spy and implicated Julius Rosenberg in industrial and military espionage.

Timeline

Also on This Day in History

Discover more of the major events, famous births, notable deaths and everything else history-making that happened on March 6th

About the author

HISTORY.com works with a wide range of writers and editors to create accurate and informative content. All articles are regularly reviewed and updated by the HISTORY.com team. Articles with the “HISTORY.com Editors” byline have been written or edited by the HISTORY.com editors, including Amanda Onion, Missy Sullivan, Matt Mullen and Christian Zapata.

Fact Check

We strive for accuracy and fairness. But if you see something that doesn't look right, click here to contact us! HISTORY reviews and updates its content regularly to ensure it is complete and accurate.

Citation Information

Article title
The espionage trial of Ethel and Julius Rosenberg begins
Website Name
History
Date Accessed
March 24, 2025
Publisher
A&E Television Networks
Last Updated
January 24, 2025
Original Published Date
November 13, 2009

History Every Day

Sign Up for "This Day in History"

Uncover fascinating moments from the past every day! Learn something new with key events in history, from the American Revolution to pop culture, crime and more.

By submitting your information, you agree to receive emails from HISTORY and A+E Global Media. You can opt out at any time. You must be 16 years or older and a resident of the United States.