Blunt was born in Bournemouth, the third and youngest son of a vicar, the Revd (Arthur) Stanley Vaughan Blunt (1870—1929) and his wife, Hilda Violet (1880—1969), daughter of Henry Master of the Madras civil service. He was the brother of writer Wilfrid Jasper Walter Blunt and of numismatist Christopher Evelyn Blunt, and the grandnephew of poet Wilfrid Scawen Blunt.Blunt is frequently spoken of as a distant relative of Queen Mary (Mary of Teck) – generally Prince Michael of Hesse is given as their common cousin – however, the exact lineage is never produced. He was, however, demonstrably a cousin of Elizabeth Bowes-Lyon, the late Queen Mother, through his mother, Hilda V. Master, daughter of John Henry Master, son of Frances Mary Smith, sister of Oswald Smith, father of Frances Dora Smith, mother of Claude George Bowes-Lyon, 14th Earl of Strathmore and Kinghorne, father of Elizabeth Angela Marguerite Bowes-Lyon, making Blunt and the Queen Mother third cousins, by common descent from George Smith and his wife Frances Mary Mosley. The young Anthony and his two brothers Christopher and Wilfrid occasionally used to have tea with Elizabeth at the family's London home in Bruton Street, Mayfair - the house from which she was driven to Westminster Abbey in 1923 (when Blunt was 16) to marry the Duke of York, later King George VI.

Blunt's vicar father was assigned to Paris with the British Embassy chapel, and so moved his family to the French capital for several years during Blunt's childhood. The young Anthony became fluent in French, and experienced intensely the artistic culture closely available to him, stimulating an interest which would last a lifetime and form the basis for his later career.He was educated at Marlborough College, where he joined the College's secret 'Society of Amici', in which he was a contemporary of Louis MacNeice (whose unfinished autobiography The Strings are False contains numerous references to Blunt), John Betjeman and Graham Shepard. He was remembered by Historian John Edward Bowle, a year ahead of Blunt at Marlborough, as an intellectual prig, too preoccupied with the realm of ideas. He thought Blunt had too much ink in his veins and belonged to a world of rather prissy, cold-blooded, academic puritanism.

He won a scholarship in mathematics to Trinity College, Cambridge. At that time, scholars in Cambridge University were allowed to skip Part 1 of the tripos and complete Part 11 in two years. However they could not earn a degree in less than three years. , So Blunt spent four years at Trinity and switched to Modern Languages, eventually graduating in 1930 with a First Class degree, He taught French in Cambridge and became a Fellow of the college in 1932. His graduate research was in French art history and he traveled frequently to continental Europe in connection with his studies.Like Guy Burgess Blunt was known to be homosexual, which was a criminal activity at that time in Britain. Both were members of the Cambridge Apostles also known as the Conversazione society a Cambridge clandestine discussion group of 12 undergraduates, mostly from Trinity and Kings Colleges who considered themselves to be the brightest minds in the University. Many were homosexual and Marxist at that time. Amongst other members also later accused of being part of the Cambridge spy ring were the American Michael Whitney Straight and Victor Rothschild who later worked for MI5. Rothschild gave Blunt £100 to purchase "Eliezer and Rebecca" by Nicholas Poussin. The painting was sold by Blunt's executors in 1985 for £100,000 (totalling £192,500 with tax remission The Art Fund - Eliezer and Rebecca) and is now in the Fitzwilliam Museum. Fitzwilliam Museum - OPAC Record

There are a number of versions as to how Blunt was recruited to the NKVD. As a Cambridge don, Blunt visited the Soviet Union in 1933, and was possibly recruited in 1934. Many sources suggest that Blunt remained at Cambridge and served as a talent-spotter. He may have identified Burgess, Kim Philby, Donald Maclean,John Cairncross and Michael Straight,who were all undergraduates at Trinity College, a few years younger than himself, as potential spies for the Soviets. But Blunt himself said in his public confession that it was Burgess who converted him to the Soviet cause, after both had left Cambridge. Both were members of the Cambridge Apostles, and Burgess could have recruited Blunt or vice versa either at Cambridge University or later when both worked for British intelligence.

With the invasion of Poland by German and Soviet forces Blunt joined the British Army in 1939. During the phony war he served in France in the intelligence corps. When the Wehrmacht drove British forces back to Dunkirk, in May 1940 he was evacuated, by the Royal Navy. During 1940, he was recruited to MI5, the Security Service.. Before the war MI5 mostly employed former Indian policemen, for it was in India that the British Empire faced security threats. But now much new brainpower arrived. MI5 may have known Blunt`s views for an officer later claimed that it had been virtually running the Communist Party of Great Britain and complained about the cost of pension payments to its retired infiltrators.

Blunt passed the results of ULTRA intelligence from decrypted Enigma intercepts of Wehrmacht radio traffic from the Russian front. He has also admitted to passing details of German spy rings, operating in the Soviet Union.Ultra was primarily working on the Kriegsmarine naval codes, which eventually helped win the battle of the Atlantic. But as the war progressed Wehrmacht army codes were also broken. Powerful receivers could pick up transmission from Berlin, relating to German war plans. But there was great risk that if the Germans found out that their codes had been compromised, they would change the settings of the Enigma wheels, blinding the codebreakers.

Full details of the entire Operation Ultra were fully known by only four people, only one of whom routinely worked at Bletchley Park. Dissemination of Ultra information did not follow usual intelligence protocol, but maintained its own communications channels. Military intelligence officers gave intercepts to Ultra liaisons, who in turn forwarded to the intercepts to Bletchley Park. Information from decoded messages was then passed back to military leaders through the same channels. Thus, each link in the communications chain knew only one particular job, and not the overall details of Ultra. Nobody outside Bletchley Park knew the source.

John Cairncross another of the Cambridge Five was posted from MI6 to work at Bletchley Park. Blunt admitted to recruiting Cairncross and may well have been the cut-out between Cairncross and the Soviet controllers. For although the Soviet Union was now an ally, Russians were not trusted. Some information concerned German preparations and detailed plans for the Battle of Kursk, the last decisive encounter on the Eastern Front. Malcolm Muggeridge, himself a wartime British agent, recalls meeting Kim Philby and Victor Rothschild, a friend of Blunt since Trinity College, Cambridge. He reported that at the Paris meeting in late 1955 Rothshchild argued that much more Ultra material should have been given to Stalin. For once, Philby reportedly dropped his reserve, and agreed.

During the war, Blunt attained the rank of major.In the final days of World War II, in Europe Blunt made a successful secret trip to Schloss Friedrichshof in Germany to retrieve sensitive letters between the Duke of Windsor and Adolf Hitler and other leading Nazis. George VI asked Blunt who worked part-time at the Royal Library to conduct the Royal Librarian, Owen Morshead, to Friedrichshof in March 1945 to liberate letters to the Empress Victoria, a daughter of Queen Victoria and mother to Kaiser Wilhelm. Papers rescued by Morshead and Blunt, were deposited in the Royal Archives.

Some people knew of Blunt`s role long before his public exposure. In 1948, a demobbed army officer, Philip Hay, came to Buckingham Palace to be interviewed for the post of Private Secretary to the widowed Princess Marina, Duchess of Kent. As he walked down a red-carpeted corridor with Sir Alan Lascelles, the King's private secretary, they passed Blunt in silence. When they were out of earshot, Sir Alan whispered to Hay: 'That's our Russian spy.'

According to MI5 papers released in 2002, Moura Budberg known as the Russian Mata Hari and suspected of being a double agent reported in 1950 that Blunt was a member of the Communist Party, but this was ignored. According to Blunt himself, he never joined, because Burgess persuaded him that he would be more valuable to the anti-fascist crusade by working with Burgess. It is possible that his activities were already known to the authorities shortly after the war. He was certainly on friendly terms with Sir Dick White, the Head of MI5 and later MI6, in the 1960s, and they used to spend Christmas together with Victor Rothschild in Rothschild's house in Cambridge.

His NKVD control had also become suspicious at the sheer amount of material he was passing over and suspected him of being a triple agent. Later, he was described by a KGB officer as an 'ideological shit'.

With the defection of Burgess and Maclean to Moscow in May 1951, Blunt came under suspicion. He had been a friend of Burgess, since Cambridge. Maclean was in imminent danger due to decryptions from VENONA. Burgess returned on the Queen Mary to Southampton after being suspended from the British Embassy in Washington for his driving conduct. He was to warn Maclean who now worked in the Foreign Office, but was under surveillance and isolated from secret material. Blunt collected Burgess at Southampton Docks and took him to stay at his flat in London, although he later denied that he had warned the defecting pair. Blunt was interrogated by MI5 in 1952, but gave little, if anything, away.Arthur Martin and Jim Skardon had interviewed Blunt eleven times since 1951, but Blunt had admitted nothing.

Blunt was greatly distressed by Burgess` flight and on Monday May 28 1951 confided in his friend Goronwy Rees, a fellow of All Souls College, Oxford, who had briefly supplied the NKVD with political information in 1938-9. Rees suggested that Burgess had gone to the Soviet Union because of his violent anti-Americanism and belief that America would involve Britain in a Third World War, and that he was a Soviet agent. Blunt suggested that this was not sufficient reason to denounce Burgess to MI5. He pointed out that “Burgess was one of our oldest friends and to denounce him would not be the act of a friend.” Blunt quoted E.M.Forster`s belief that country was less important than friendship. He argued that “Burgess had told me he was a spy in 1936 and I had not told anyone.”

In January 1964, Arthur Martin from MI5 interviewed Michael Straight the third and youngest son of Willard Straight, an investment banker with J. P. Morgan and later owner and editor of The New Republic and chairman of the National Endowment for the Arts)., Straight, an American had been a friend of Blunt at Trinity College, Cambridge,.where he was also an Apostle. Straight claimed to have been recruited by him at Trinity in 1937 and that. Blunt gave him orders from the KGB to get a job in Wall Street Straight had a private income and instead took unpaid work with the State Department in Washington. He claimed that of the few essays that he passed to the Soviets one was an attack on the Molotov-Ribbentrop pact, in 1939.

Straight did not confess in 1951, when interviewed about Burgess and Maclean. But when offered a job in the Kennedy Administration, in 1963 Straight revealed his knowledge of Blunt. Martin, went to see Blunt again with Straight`s evidence and this time Blunt confessed. Queen Elizabeth II was informed shortly thereafter. He admitted to being a Soviet agent and named John Cairncross, Peter Ashby, Brian Symon and Leonard Henry Long as spies he had recruited. Long had also been a member of the Communist Party and an undergraduate at Trinity College, Cambridge. During the war he served in M14 military intelligence in the War Office, with responsibility for assessing German offensive plans. He passed analyses but not original material relating to the Eastern Front to Blunt.Mrs Thatcher later declared that there would be no intention of prosecuting Long. In return for Blunt's full confession, the British government agreed to keep his spying career an official secret for fifteen years, and granted him full immunity from prosecution.

Martin was disappointed that MI5 Director-General Roger Hollis and Attorney General Sir John Hobson did not put Blunt on trial. He again argued that there was still a Soviet spy working at the centre of MI5, but Hollis thought Martin's suggestion was highly damaging to the organization, and ordered Martin to be suspended from duty, soon afterwards terminating his employment in MI5 and sending him to MI6. In Peter Wright's best-selling 1987 book Spycatcher, Wright argued that Hollis was the best fit for the possible Soviet spy in MI5 though historian Peter Hennessy has shown there is little credence to this assertion.Blunt`s life was little affected. In 1966, two years after his secret confession, Noel Annan, provost of King's College, Cambridge, held a dinner party for Labour Home Secretary Roy Jenkins, Ann Fleming, widow of James Bond author Ian Fleming, and Victor Rothschild and his wife Tess. The Rothschilds brought their friend and lodger - Blunt. All had had wartime connections with British Intelligence, Jenkins at Bletchley Park. Was this an effort by his friends to obtain immunity for Blunt?

Blunt's role was represented under the name Maurice; in Andrew Boyle's book, Climate of Treason in 1979. Maurice was taken from the E. M. Forster novel of that name: he was a homosexual and spy. Blunt tried to prevent the book being published which fact was duly reported in the magazine Private Eye. This drew attention to Blunt . Prime Minister Margaret Thatcher revealed Blunt`s wartime role in the House of Commons, a week later. Sir Bernard Ingham, Thatcher`s private secretary suggested "I believe she did it because she didn't see why the system should cover things up.This was early in her Prime Ministership. I think she wanted to tell the Civil Service that the politicians decide policy, not the system. She wanted them to know who was boss."

For weeks after Thatcher’s announcement, Blunt was hunted by the Press. Once found, he was besieged by photographers. Blunt had recently given a lecture at the invitation of Francis Haskell Oxford University`s professor of art history. Haskell had a Russian mother and wife and had graduated from King’s College, Cambridge. To the Press this made him an obvious suspect. They repeatedly telephoned his home in the early hours of the morning, using the names of his friends and claiming to have an urgent message for ‘Anthony’.

Although outwardly calm, the sudden exposure shocked Blunt. His former pupil, art critic Brian Sewell said at the time “He was so businesslike about it; he considered the implications for his knighthood and academic honours and what should be resigned and what retained. What he didn't want was a great debate at his clubs, the Athenaeum and the Travellers. He was incredibly calm about it all.Queen Elizabeth II stripped Blunt of his knighthood, and he was removed as an Honorary Fellow of Trinity College. Blunt himself claimed that he went into hiding in London. After his BBC Television confession at the age of 72, he broke down in tears. However, he failed to sense public feeling until one day in February 1980, watching a film in Notting Hill, he was identified and booed out of the cinema. That same month, John Gaskin, a Scot and former bandsman in the Irish Guards and his partner since 1953, threw himself from a sixth-floor balcony but survived, as his fall was broken by iron railings.

Blunt died from a heart attack at his home in London in 1983, aged 75.

Blunt withdrew from society and seldom went out after his exposure. His friend Tess Rothschild suggested that he occupy his time, writing his memoirs. Brian Sewell, his former pupil, said they remained unfinished because he had to consult the newspaper library in Colindale, Edgware North London, to check facts. He was unhappy at being recognised. “I do know he was really worried about upsetting his family,” suggests Sewell. “I think he was being absolutely straight with me when he said that if he could not verify the facts there was no point in going on.” Blunt stopped writing in 1983 leaving his memoirs to his sexual partner John Gaskin, who kept it for a year and gave it to Blunt`s executor John Golding , a fellow art historian.John Golding handed it to the British Library,insisting that it should not to be released for 25 years. It was finally made available to readers on 23 July 2009. Golding explains: “'I did so because, although most of the figures mentioned were dead, their families might not like it. It covers his Cambridge days and there are a number of names. They weren't all spies, but Communism was common among intellectuals in the Thirties.”In the typed manuscript, Blunt conceded that spying for Communist Russia was "the biggest mistake of his life":

"What I did not realise is that I was so naïve politically that I was not justified in committing myself to any political action of this kind. The atmosphere in Cambridge was so intense, the enthusiasm for any anti-fascist activity was so great, that I made the biggest mistake of my life."

The memoir revealed little that was not already known about Blunt, When asked whether there would be any new or unexpected names? John Golding replied “I'm not sure. It's 25 years since I read it, and my memory is not that good.”Although ordered by the KGB to defect with Maclean and Burgess to protect Philby, in 1951 Blunt realised “quite clearly that I would take any risk in [Britain], rather than go to Russia." After he was publicly exposed, he claims to have considered suicide but instead turned to "whisky and concentrated work".

Throughout the time of his activities in espionage, Blunt's public career was in the History of Art, a field in which he gained prominence. In 1940, most of his fellowship dissertation was published under the title of Artistic Theories in Italy, 1450-1600. In 1945, he was given the esteemed position of Surveyor of the King's Pictures, and later the Queen’s Pictures (after the death of King George VI in 1952), one of the largest private collections in the world. He held the position for 27 years, was knighted as a KCVO in 1956 for his work in the role, and his contribution was vital in the expansion and cataloguing of the Queen’s Gallery, which opened in 1962.

In 1947 he became both Professor of the History of Art at the University of London, and the director of the Courtauld Institute of Art, University of London, where he had been lecturing since the spring of 1933, and where his tenure in office as director lasted until 1974. This position included the use of a live-in apartment on the premises. During his 27 years at the Courtauld Institute, Blunt was respected as a dedicated teacher, a kind superior to his staff. His legacy at the Courtauld was to have left it with a larger staff, increased funding, and more space, and his role was central in the acquisition of outstanding collections for the Courtauld's Galleries. He is often credited for making the Courtauld what it is today, as well as for pioneering art history in Britain, and for training the next generation of British art historians.

In 1953, Blunt published his book Art and Architecture in France, 1500-1700, and he was in particular an expert on the works of Nicolas Poussin, writing numerous books and articles about the painter, and serving as curator for a landmark exhibition of Poussin at the Louvre in 1960, which was an enormous success. He did not, however, limit his research in the areas of Italian art and French art, but also wrote on topics as diverse as William Blake, Pablo Picasso, the Galleries of England, Scotland, and Wales. He also catalogued the French drawings (1945), G. B. Castiglione and Stefano della Bella drawings (1954) Roman drawings (with H. L. Cooke, 1960) and Venetian (with Edward Croft Murray, 1957) drawings in the collection of the Queen, as well as a supplement of Addenda and Corrigenda to the Italian catalogues (in E. Schilling's German Drawings).He attended a summer school in Sicily in 1965, leading to a deep interest in Sicilian architecture, and in 1968 he wrote the only authoritative and in-depth book on Sicilian Baroque. From 1962 he was engaged in a dispute with Denis Mahon regarding the authenticity of a Poussin work which rumbled on for several years. Mahon was shown to be correct. Blunt was also unaware that a painting in his own possession was also by Poussin.. It has been suggested that Blunt could not accept that Poussin may have produced inferior work.

Notable students who have been influenced by Anthony Blunt include Brian Sewell (an art critic for the Evening Standard), Ron Bloore, Nicholas Serota, Neil Macgregor, the former editor of the Burlington magazine, former director of the National Gallery and the current director of the British Museum, John White (art historian), Sir Alan Bowness (who ran the Tate Gallery), John Golding (who wrote the first major book on Cubism), Reyner Banham (an influential architectural historian), John Shearman (the ‘world expert’ on Mannerism and the former Chair of the Art History Department at Harvard University), Melvin Day (former Director of National Art Gallery of New Zealand and Government Art Historian for New Zealand ), Christopher Newall (an expert on the Pre-Raphaelites), Michael Jaffé (an expert on Rubens), Michael Mahoney (former Curator of European Paintings at the National Gallery of Art, Washington, D.C., and former Chair of the Art History Department at Trinity College, Hartford), Lee Johnson (an expert on Eugène Delacroix), and Anita Brookner (an art historian and novelist).

Among his many accomplishments, Blunt also received a series of honorary fellowships, became the National Trust picture advisor, put on exhibitions at the Royal Academy, edited and wrote numerous books and articles, and sat on every influential art committee.

After Mrs Thatcher announced Blunt’s espionage, he continued his art historical work by writing and publishing a Guide to Baroque Rome (1982) and completing a manuscript (apparently lost by the publisher after they sent it to a German art historian) on the architecture of Pietro da Cortona.

Many of his publications are still seen today by scholars as integral to the study of art history. His writing is lucid, and is based largely on art and architecture in context of their place in history. In his book Art and Architecture in France, for example, he begins each section with a brief depiction of the social, political and/or religious contexts in which works of art and art movements are emerging. And in Blunt’s Artistic Theory in Italy, 1450-1600, he clearly explains the motivational circumstances involved in the transitions between the High Renaissance and Mannerism. His ground-breaking work and logical method to art history have served as resources for many scholars, including Todd P. Olson and John Beldon Scott.

A Festschrift Studies in Renaissance and Baroque Art presented to Anthony Blunt on his 60th Birthday, Phaidon 1967 (introduction by Ellis Waterhouse) contains a full list of his writings up to 1966.

Major works include:

• Anthony Blunt, François Mansart and the Origins of French Classical Architecture, 1941.
• Anthony Blunt, Art and Architecture in France, 1500-1700, 1953 and many subsequent editions.
• Anthony Blunt, Nicolas Poussin. A Critical Catalogue, Phaidon 1966
• Anthony Blunt, Nicolas Poussin, Phaidon 1967 (new edition Pallas Athene publishing, London, 1995).
• Anthony Blunt, Sicilian Baroque, 1968 (ed. it. Milano 1968; Milano 1986).
• Anthony Blunt, Picasso's Guernica, Oxford University Press, 1969.
• Anthony Blunt, Neapolitan Baroque and Rococo Architecture, London 1975 (ed. it. Milano 2006).
• Anthony Blunt, Baroque and Rococo Architecture and Decoration, 1978.
• Anthony Blunt, Borromini, 1979 (ed. it. Roma-Bari 1983).
• Anthony Blunt, L'occhio e la storia. Scritti di critica d'arte (1936—1938), a cura di Antonello Negri, Udine 1999.

Important articles after 1966:

• Anthony Blunt, 'Rubens and architecture,' Burlington Magazine, 1977, 894, pp. 609—621.
• Anthony Blunt, 'Roman Baroque Architecture: the Other Side of the Medal,' Art history, no. 1, 1980, pp. 61—80 (includes bibliographical references).

A Question of Attribution is a play written by Alan Bennett about Blunt, covering the weeks before his public exposure as a spy, and his relationship with Queen Elizabeth II. After a successful run in London's West End, it was made into a television play directed by John Schlesinger and starring James Fox, Prunella Scales and Geoffrey Palmer. It was aired on the BBC in 1991. This play was seen as a companion to Bennett's 1983 television play about Guy Burgess, An Englishman Abroad.

Blunt: The Fourth Man is a 1985 film starring Ian Richardson, Anthony Hopkins, Michael Williams, and Rosie Kerslake, covering the events of 1951 when Guy Burgess and Donald Maclean went missing.

The Untouchable, a 1997 novel by John Banville, is a roman à clef based largely on the life and character of Anthony Blunt; the novel's protagonist, Victor Maskell, is a loosely disguised Blunt, although some elements of the character are based on Louis MacNeice.

A Friendship of Convenience: Being a Discourse on Poussin's "Landscape With a Man Killed by a Snake", is a 1997 novel by Rufus Gunn set in 1956 in which Blunt, then Surveyor of the Queen's Pictures, encounters Joseph Losey, a film director fleeing McCarthyism.

Cambridge Spies is a 2003 four-part BBC television drama concerning the lives of the Cambridge Four from 1934 to the defection of Guy Burgess and Donald Maclean to the Soviet Union.