Lindsay Powell has been investigating the death of Germanicus Julius Caesar (16 BC-AD 19) some 1,994 years ago in Antioch, Syria.

Germanicus’s wife, Agrippina insisted her husband had been murdered and the cause of the general’s death has puzzled historians for thousands of years.

But at last, author and historical detective Mr Powell thinks he has found the answer.

Mr Powell’s latest book, Germanicus: The Magnificent Life and Mysterious Death of Rome’s Most Popular General, delves into the circumstances surrounding the death, and examines new evidence.

A number of causes were examines, such as murder, poisoning or a virus.

Mr Powell’s conclusions point towards a virus the general picked up while in Egypt.

This is supported by reports that he frothed at the mouth at the time of his death, and his body was blue in colour.

Mr Powell said: “He had just returned to Syria from a long trip to Egypt. In the first century the East was a dangerous place.” Mr Powell presented his findings to a panel of professors at the department of classics at Reading University, on Wednesday last week. He said he wanted to go ‘into the lions’ den’, to see if his findings would stand up to professional scrutiny, which he happily added they did.

Germanicus was a general, and the adopted son of Emperor Tiberius, whose death was widely believed to have been at the hands of the governor of Syria, Calpurnius Piso.

However, many believed the emperor had a hand in Germanicus’ death.

Germanicus and Agrippina were the glamorous couple of their time, famous and widely loved. Germanicus’s son Caligula went on to become the third emperor of the Roman Empire.