[5] In 1940 Cockburn's Security Service file said that "In 1939 he was a leading British Communist Party member and was said to be a leader of the Comintern in Western Europe".

[8] He became a journalist with The Times and worked as a foreign correspondent in Germany and the United States before he resigned in 1933 to start his own newsletter, The Week.

It has been said that during his spell as a sub-editor on The Times, Cockburn and colleagues competed (with a small prize for the winner) to write the dullest printed headline.

In 1936, Harry Pollitt, General Secretary of the Communist Party of Great Britain, asked him to cover the Spanish Civil War.

Cockburn's reporting in Spain, as "Frank Pitcairn", was heavily criticised by George Orwell in his 1938 memoir Homage to Catalonia.

[14] This hoax was intended to persuade the French prime minister that Francisco Franco's forces were weaker than they appeared and thus make the Republicans seem worthier candidates for help in obtaining arms.

In a 1937 article in The Week, Cockburn coined the term "Cliveden set" to describe what he alleged to be an upper-class pro-German group that exercised influence behind the scenes.

[citation needed] Among his novels were Beat the Devil (originally under the pseudonym James Helvick), The Horses, Ballantyne's Folly,[19] and Jericho Road.

Beat the Devil was made into a film in 1953 by the director John Huston, who paid Cockburn £3,000 for the rights to the book and screenplay.

Cockburn's three sons are all journalists: Alexander, who moved to the US, wrote for Village Voice, the Nation and CounterPunch; Andrew became the Washington editor of Harper'; Patrick also published a biography of his father.