Michael Grant, who died on Monday aged 89, was a don at Cambridge, professor of humanity (Latin) at Edinburgh, and vice-chancellor at the Universities of Khartoum and Queen’s, Belfast, but was best known as a prolific popularizer of ancient history who published nearly 50 books on the Greeks, Romans, and early Christianity.

Grant was always a lucid and erudite writer, who took the view that a study of the classical world was both “infinitely worth studying in its own right, without any consideration of modern analogies” and also that “without Latin, people are handicapped because they do not understand their past, and cannot therefore effectively plan their futures.”

This attitude did nothing to impede his range, nor his appeal to the ordinary reader as well as the academic professional. As well as scholarly publications on the coinage of Rome (he was a distinguished numismatist), he produced biographies of Julius Caesar, Nero, Herod, Cleopatra, Jesus, St Peter and St Paul; accounts of the literature, history, art, mythology and social life of Greece and Rome; and found time to examine the Middle Ages and ancient Israel.

Books such as “The Twelve Caesars” (1975) and “Gladiators” (which was reissued recently after Ridley Scott’s film) sold well in Penguin editions and enabled him to boast of a position as “one of the very few freelances in the field of ancient history” and, for the last 30 years or so, to work from his home in Italy.

There was scarcely an aspect of ancient life which did not receive Grant’s attention: “The History of Rome” (1978); “The Jews in the Roman World” (1973); “Art in the Roman Empire” (1995); “The Classical Greeks” (1989); “The Hellenistic Greeks” (1990) and many more were ground out by his pen.

Michael Grant was born in London on November 21 1914, the only son of Colonel Maurice Grant, who had served in the Boer War and later wrote part of its official history, before covering the Balkan Wars for the Daily Mail and rising to become an obituarist – though he was sacked for failing to get up in the night to update Kitchener’s obituary in 1916. His mother Muriel was of Danish stock, and descended from Jorgen Jorgensen, who staged an unsuccessful coup in Iceland in 1809.

At school he particularly remembered his time at Harrow, where one of his masters was E.V.C. Plumptre, a precise figure. When discussing the novel “Quo Vadis” – which took its title from the reputed words of the resurrected Christ to St Peter – he commented: “A classical Roman would have said ‘Quo Is.’ What a pity that our Lord spoke such late and inferior Latin.” Young Grant also made visits to Rome’s ancient sights, which made an immense impact on him.

He went up to Trinity, Cambridge, in 1933, where he wasted his first year, but buckled down after failing to be short listed for a scholarship. Having won a slew of awards and graduated, he compiled a thesis as a research student (later published as “From Imperium to Auctoritas”), and traveled widely – aware that the impending war would soon make that impossible. In 1938, Grant was duly elected a Fellow of Trinity.

But then, as Grant noted in his autobiography “My First Eighty Years” (1994): “There was a singularly unpleasant war on in 1939-45 and … the Army seemed the right place to be in.”

He trained with Anthony Blunt, who went into MI 5 (“a most unsuitable job, as it turned out, to give to him”) and then worked beside David Niven as a duty officer at the War Office, where he was once compelled to rouse the Chief of the imperial general staff, Field Marshal Lord Ironside, to tell him of the invasion of Norway and Denmark. He opened his call with the day’s codeword, “Viking”, to be greeted with the answer: “What the hell are you talking about?”

Grant was transferred to France, where he had the embarrassing task of organizing “nocturnal amusements” for his commanding officer and, exhausted, the next day, lunched with the Duke of Windsor, who – to the commanding officer’s horror – wore suede shoes.

He was then transferred to the British Council in Turkey, where he got to know “Cicero”, the German spy who was valet to the British ambassador, Sir Hughe Knatchbull-Hugessen. Grant attributed Cicero’s success to his rudeness, which meant no one suspected him. Grant himself succeeded (by eating a packet of butter before going out to meet ministers) in keeping up with demanding Turkish drinking habits, though not in persuading the country to join the allies. He also got his friend the historian Steven Runciman his first job, at Ankara University.

After the war, Grant and his Swedish wife Anne-Sophie, whom he had met and married in Turkey, returned to England, and returned briefly to Cambridge, where he supervised students on Athenian history while Bertrand Russell, who shared the room, relaxed before dinner.

He also became a figure of suspicion after taking some students to Rome, where he bought them a drink and took them to the church of San Pietro in Vincoli – thus, in their view, attempting to seduce them with both alcohol and Papist idolatory. He received some teasing for once wearing an overcoat beneath his gown to guard against the cold.

Between 1956 and 1958, Grant took a sabbatical to become first vice-chancellor of the University of Khartoum, which he enjoyed, though arguments over “Sudanization” and the Suez crisis did much to make his life there tiresome. He later regretted the restrictions imposed on the university by fundamentalist Islam, and the failures of Sudan’s government.

In 1966, Grant and his wife moved to Italy, where he bought a 16th-century house from Paolo Rossi, the minister for education. It was situated near Lucca, where Pompey, Crassus, and Caesar met in 56 B.C. to hammer out differences which had grown up during the First Triumvirate; it was also convenient for Etruscan remains and for the amphitheatre (dating from 79-95 A.D.) nearby. From his book-lined study there, Grant continued to turn out numerous works.

His most recent book was “Sick Caesars” (2000).