蒙塔古先后就读过威斯敏斯特公学、国王学院、剑桥大学，曾从事动物学研究。His directorial career began in the late 1920s with a short film about table tennis. With Sidney Bernstein he established the London Film Society in 1925, the first film club devoted to showing art films and independent films. Montagu became the first film critic of The Observer and the New Statesman. He did the post-production work on Alfred Hitchcock’s The Lodger in 1926 and was hired to Gaumont-British in the 1930s, working as a producer on a number of the Hitchcock thrillers.
Montagu joined the Fabian Society in his youth, then the British Socialist Party and then the Communist Party of Great Britain. This brought him into contact with Russian film makers. In 1930 he accompanied his friend Sergei Eisenstein to New York and Hollywood; later in the decade Montagu made a number of compilation films, including Defence of Madrid (1936) and Peace and Plenty (1939) about the Spanish Civil War. He directed also the documentary Wings Over Everest (1934) with Geoffrey Barkas. As a political figure and for a time a communist, much of his work at the time was on low budget, independent political films. By World War II, however, he made a film for the Ministry of Information. After the war Montagu worked as a film critic and reviewer.
In 1933, Montagu was a founder member of the Association of Cinematograph and Television Technicians, holding various positions in the union until the 1960s. He also held post on the World Council of Peace. He was awarded the Lenin Peace Prize in 1959.
Montagu was identified as a prewar spy for the GRU after the decryption of Venona messages, but this has never been confirmed. His brother of identical background Ewen Montagu was a spy for MI6, author of The Man Who Never Was and mastermind of the highly successful conter-Nazi Operation Mincemeat.
- 《今日乒乓球》Table Tennis Today (1924)
- 《乒乓球》Table Tennis (1936)
- 《电影世界》Film World (1964)
- 《与爱森斯坦在好莱坞》With Eisenstein in Hollywood (1968)
- 《幼子》The Youngest Son (1970)