Cedric Henning Belfrage (8 November 1904 – 21 June 1990) was an English film critic, journalist, writer and political activist.

[5] While still a Cambridge student, Belfrage began a writing career as a film critic, with a first article in Kinematograph Weekly in 1924.

[9] He decided to make the United States his home and took out first papers for citizenship in 1937, although he failed to complete the process within the statutory seven-year time limit.

[7] Thereafter, he maintained a friendly but critical relationship as a so-called "fellow traveler" outside party membership and discipline, recalling in his 1978 memoir that for "temperamentally argumentative" adherents of socialism such as himself, such status as a "non-Communist, non-anti-Communist... suited us better.

"[11] Despite his non-membership in the American Communist Party, Belfrage remained a believer that it functioned as "the core of the radical movement.

[15] In 1948, Belfrage co-founded, together with James Aronson and John T. McManus, a radical weekly newspaper called the National Guardian.

The interview covered his relations with CPUSA General Secretary Earl Browder, Jacob Golos, V. J. Jerome, and surveillances and documents about Scotland Yard and the Vichy Government of France.

[25] In 1995, intercepts decrypted by Venona – a project between the US and British intelligence services to decipher Soviet messages – were made public.

Seven Venona decrypts reference UNC/9 in passing conversations between Belfrage's bureau chief and Winston Churchill on to the Soviets.

[1] In August 2015, Christopher Andrew, professor of modern history at Cambridge and official historian of MI5 accessed documents released from the UK National Archive which confirmed that Belfrage worked for the Secret Intelligence Service (MI6) during the war and also spied for the Soviet Union.