23 February: On this day in history

And it was one of these men, his son-in-law Galerius – a religious conservative who had commanded the army against the Persians – who persuaded Diocletian that it was time to crack down on the Christians.

After an argument about their religious policy in the winter of 302, Galerius and Diocletian decided to resolve it by consulting the oracle of Apollo at Didyma. The oracle’s verdict came back: the presence of the “just on Earth”, it said, was preventing it from speaking. By this, Galerius insisted, it meant the Christians.

On 23 February, Diocletian made his move. It was the feast-day of Terminus, the god of the boundary-marker – an appropriate day to begin the termination of Christianity. At first he ordered that the new Christian church in the eastern city of Nicomedia be destroyed and its treasures seized. But the next day he went further. In his Edict Against the Christians, Diocletian ordered that all Christian churches, books and relics be obliterated. Christians were banned from religious meetings or from appearing in court, while all Christian senators, civil servants and officers were stripped of their titles.

Although Diocletian ordered that the edict be carried out “without bloodshed”, officials in the east in particular quickly resorted to the death penalty, burning Christians alive if they resisted. But the truth was that Christianity was too deeply embedded in Roman culture to be rooted out. As one historian puts it, the persecution was “too little, too late”. | Written by Dominic Sandbrook

23 February AD 532: Justinian begins work on a dazzling holy building

Istanbul’s exquisite Hagia Sophia rises from the ashes

As anybody who has been to Istanbul will know, the Hagia Sophia, now almost 1,500 years old, remains one of the most extraordinary buildings on the planet. First a church, then a mosque, and now a museum, it has never lost its power to dazzle visitors. “It exults in an indescribable beauty,” wrote the Byzantine historian Procopius. “Whenever anyone enters this church to pray, he understands at once that it is not by any human power or skill, but by the influence of God, that this work has been so finely turned.”

Human skill did play a part, though. Today’s Hagia Sophia was actually a replacement for a church that had burned down during rioting in January AD 532. A few weeks later, on 23 February, the Emperor Justinian ordered work to begin on a new, superior building, designed by the mathematicians Isidore of Miletus and Anthemius of Tralles. Their goal was to produce the most beautiful building in the world, with a vast, free-floating dome, lined with gold, to suggest the immensity of heaven.

The Hagia Sophia, with its immense dome and richly decorated interior, was Emperor Justinian’s crowning achievement and an emphatic statement of late Roman might.

Stone and marble were imported from across the empire and, amazingly, the work took less than six years. There were of course no health and safety regulations in those days, which was probably bad news for the two teams of 5,000 builders, each of which worked on one side.

By the end of AD 537, the building was ready for consecration. Justinian was delighted. “Solomon,” he cried out, “I have surpassed thee!” | Written by Dominic Sandbrook

23 February 1643

Queen Henrietta Maria wrote to her husband, Charles I, describing how she landed under fire at Bridlington in Yorkshire bringing arms and ammunition purchased overseas for the royalist war effort in the Civil War.

23 February 1648

Birth in Devon of Arabella Churchill, the mistress of James II and elder sister of John Churchill, the future first Duke of Marlborough.

23 February 1792

Sir Joshua Reynolds, English portrait painter and the first president of the Royal Academy, died aged 68. He is buried in the crypt of St Paul's Cathedral.

23 February 1817

Birth of Victorian artist George Frederick Watts.

23 February 1820

The Cato Street Conspiracy to assassinate the British cabinet while they were supposedly at a dinner in Grosvenor Square was uncovered. Five conspirators were later executed including Arthur Thistlewood, the leader.

23 February 1821

English poet John Keats, author of works including 'Ode to a Nightingale', 'La Belle Dame Sans Merci' and 'To Autumn' died of consumption in Rome. He is buried in the city's Protestant cemetery.

23 February 1859

Death in Paris of Polish poet, novelist and playwright Zygmunt Krasinski. Along with Adam Mickiewicz and Juliusz Slowacki he is considered one of the three 'National Bards' of Polish literature.

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