2 September: On this day in history

2 September 1859: A dramatic solar storm lights up the Earth

The “Carrington Event” causes auroras and telegraph chaos

When British amateur astronomer Richard Carrington went into his private observatory, connected to his home near London, shortly before noon on 1 September 1859, he intended to sketch sunspots. But his attention was seized by something he had never seen before on the Sun: “two patches of intensely bright and white light”. Carrington – and at the same time, fellow astronomer Richard Hodgson – had just witnessed a massive solar flare. It lasted only a few minutes, but the subatomic particles it hurled at Earth would cause the greatest recorded geomagnetic storm in history, peaking the next day.

The storm, now known as the Carrington Event, lit up the sky as if it were on fire and caused colourful and intense auroras, which occur near the poles, to be seen around the world. The northern lights (Aurora Borealis) were visible as far south as the Caribbean, while the southern lights (Aurora Australis) were observed in Santiago, Chile. The spectacular display of bright lights continued throughout the night, with reports of people reading their newspapers without artificial illumination and people getting up and ready for work hours too early.

The more severe consequence was that the electromagnetic radiation wreaked havoc with technology, especially the thousands of miles of telegraph communication lines around the world. The colossal surge of energy caused systems to fail, fires to break out and sparks to shower from telegraph machines. The atmosphere had become so charged that a bizarre phenomenon occurred: some operators reported that they were able to send and receive messages even after disconnecting their power supply, using only the “auroral current”.

According to late 20th-century analysis of ice core samples, which would have been ionised by the solar particles, the Carrington Event was the most intense geomagnetic storm for 500 years. If one of similar size happened today in a world reliant on technology more sophisticated than the telegraph, the impact could be catastrophic. | Written by Dominic Sandbrook

2 September 1870: Napoleon III surrenders to the Prussians

The ailing French emperor suffers a humiliating defeat at the battle of Sedan

The first two days of September 1870 were ones of abject humiliation for France. Six weeks earlier, when Napoleon III had declared war on Prussia, crowds had packed the streets of Paris chanting “To Berlin! To Berlin!” But by the time Napoleon’s army arrived at Sedan, in the Ardennes, the war was going badly. Early on 1 September battle began in earnest. Within hours it was clear the French were finished.

Already a sick man, 62-year-old Napoleon spent much of the day in a state of helpless paralysis. “If this man has not come here to kill himself, I don’t know what he has come to do,” wrote one observer.

In the afternoon, with his men under punishing fire, Napoleon ordered that the white flag be raised above the fortress of Sedan. Then he sent a message to Prussia’s Wilhelm I: “Monsieur my brother, not being able to die at the head of my troops, nothing remains for me but to place my sword in the hands of Your Majesty.”

At 6am on 2 September, Napoleon was shown into the Prussian headquarters. After signing a humiliating surrender, he was taken to a nearby castle and held in relative comfort. “It is impossible for me to say what I have suffered and what I am suffering now,” he wrote to his wife later that night.

He would, he said, have “preferred death to a capitulation so disastrous, and yet, under the present circumstances, it was the only way to avoid the butchering of 60,000 people. If only all my torments were concentrated here! I think of you, our son, and our unhappy country.” | Written by Dominic Sandbrook

2 September 1898: Churchill charges into action at Khartoum

British technology wins the day at the battle of Omdurman

It was dawn on 2 September 1898, and in Omdurman, the young Lieutenant Winston Churchill was breathing hard with excitement. After almost two decades of war in the Sudan, Herbert Kitchener’s British army had finally reached Khartoum. Against them, stood tens of thousands of Dervish swordsmen. The enemy army, remembered Churchill, was a spectacular sight. Stretching “four miles from end to end... this mighty army advanced swiftly. Above them waved hundreds of banners, and the sun, glinting on many thousands of hostile spear points, spread a sparkling cloud.”

For Churchill, the highlight of the battle was undoubtedly the swashbuckling cavalry charge of his 21st Lancers. Many of his fellows were unhorsed, and were forced to defend themselves against a tide of enemy fighters. Churchill himself was almost surrounded, and only escaped by blasting his way out with his Mauser pistol.

But the real story was the triumph of British technology. Although Kitchener’s men were outnumbered, they had Maxim machine guns and dum-dum bullets. Armed with older weapons, the Dervishes did not stand a chance. Within hours, some 10,000 of them were killed, while Kitchener lost just 48 men. “It was not a battle,” wrote one observer, “but an execution.” Afterwards, even Churchill shook his head at the sight of the fallen. “There was nothing dulce et decorum about the Dervish dead,” he wrote. "Yet these were as brave men as ever walked the Earth.” | Written by Dominic Sandbrook

2 September 1901

In a speech made at the Minnesota State Fair, Theodore Roosevelt, then vice president of the United States, uttered the famous phrase "speak softly and carry a big stick".

2 September 1939

A day after launching Germany’s invasion of Poland, Adolf Hitler orders the annexation of the formerly Free City of Danzig.

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