20 November: On this day in history

But something strange was going on. Numerian had not been seen since they had left Emesa (now called Homs, in Syria). When the soldiers asked where he was, his attendants claimed that he had an eye infection and “must protect his weakened eyes from the wind and the sun”. And the soldiers could not help noticing that, from the coach where Numerian was supposedly recovering, there drifted an increasingly disgusting stench.

Eventually, when they reached Nicomedia (in what is now Turkey) on 20 November, the truth was discovered. Numerian was dead: murdered, some said, by his own father-in-law, Aper.

“Then all fell upon Aper, whose treachery could no longer be hidden, and they dragged him before the standards in front of the general’s tent,” records the Historia Augusta. “Then a huge assembly was held and a tribunal, too, was constructed.” The question was simple: “Who would be the most lawful avenger of Numerian and who could be given to the commonwealth as a good emperor?”

The answer, it turned out, was a 40-year-old officer from Dalmatia, Diocletian, who commanded Numerian’s household troops. Diocletian duly stepped forward and drew his sword. Pointing to Aper, he said loudly: “It is he who contrived Numerian’s death” – and then buried his blade in Aper’s chest. It was, by any standards, a dramatic beginning for a Roman emperor. | Written by Dominic Sandbrook

20 November 1591

Death of Sir Christopher Hatton, lord chancellor of England and favourite of Queen Elizabeth I. Francis Drake renamed his ship Golden Hind in honour of Hatton, whose arms featured such an animal.

20 November 1230

Nicola de La Haye died in Lincolnshire. A staunch supporter of King John during the Barons' Wars, Nicola had successfully defended Lincoln Castle against a rebel army under the leadership of Prince Louis of France.

20 November 1759

Admiral Sir Edward Hawke decisively defeated a French fleet under the Comte de Conflans in Quiberon Bay near St Nazaire.

20 November 1518

Four times High Sheriff of Yorkshire, Sir Marmaduke Constable, dies at Flamborough. He became an associate of the influential Howards and fought alongside the Earl of Surrey, the head of that family, at the battle of Flodden in 1513.

20 November 1947

Princess Elizabeth marries Philip, Duke of Edinburgh, at Westminster.

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