Amis, who is considered one of the greatest British post-war writers, was placed under suspicion a few days after VE Day, while serving as a lieutenant in the Royal Corps of Signals.
He was already known by MI5 to have joined the Communist Party as an Oxford student and had been logged as a “recipient of Communist literature” after being called up, documents released by the National Archive show.
But there was a flurry of notes and letters about him after the war ended, at a time when the intelligence services were shifting their focus away from defeated Nazi Germany and towards their former allies in the Soviet Union.
A memo on Amis, dated May 13 1945, five days after VE Day, reported: “This officer came to notice in 1942 (as) a student at Oxford University when he was reported to be a very promising member of the Oxford Branch of the Communist Party.
“Since being in the Army and in BLA (British Liberation Army) he is known to have been in touch with the Headquarters of (Communist party newspaper) the Daily Worker and it is therefore reasonable to suppose that his political views have not changed in any way.”
Amis’s commanding officer had told MI5: “He is obviously well-read, but a bit young and inexperienced in the ways of the world.”
He noted that Amis had not shown “extremist tendencies” in his work, adding: “My own view is that if he tried to there are few people who would take him seriously.”
Amis was demobilised from the army the following October and resumed his scholarship at Oxford, where he formed a close friendship with the Hull poet, Philip Larkin, and went on to write his signature novel, Lucky Jim.
But he continued to be vetted by MI5 and his file shows that their involvement led to him losing a position on a lecture tour in 1955, organised by the German Information department at the Foreign Office.
It also catalogues how his politics softened in the 1950s, particularly after the 1956 Soviet invasion of Hungary. In February 1957 he wrote that he had “utterly rejected” Marxism.
Amis, the father of the novelist Martin Amis, later veered further to the right and developed a reputation as an irascible old man with a weakness for hard drinking and a relish for misogyny.