26 April: On this day in history

The plot against the Medici had been brewing for a long time. At its core were two of the city’s rival banking families, the Pazzi and the Salviati, who resented the Medici’s power. In the weeks before Easter 1478, the Pazzis had secured the tacit support not just of the priest presiding that day, the Archbishop of Pisa, but of Pope Sixtus IV himself. At an agreed moment – sources differ over whether this was at the elevation of the Host or the very end of mass – the conspirators struck.

The first blow came from one Bernardo Baroncelli, who plunged his knife into Giuliano de’ Medici with the words: “Here, traitor!” More blows followed; as observers remembered, Giuliano’s white shirt ran red with blood. Meanwhile, two knife-wielding priests had cornered Lorenzo, who, despite a blow to his neck, managed to fight them off with a short sword before a friend shut him in the sacristy for safety.

With Lorenzo still alive, the Pazzi conspiracy lost its momentum. The plotters had failed to secure the support of the townsfolk or the city guard, and very swiftly the mood turned ugly. Some of the conspirators were stripped naked and beaten to death; witnesses reported seeing the mob literally sinking their teeth into their corpses. As for Lorenzo, he ruled for another 14 years, earning the nickname ‘the Magnificent’. | Written by Dominic Sandbrook

• Read more | “They were on a level with today’s billionaires” – your guide to the Medici: bankers to the Pope, rulers of Florence, patrons of the Renaissance

26 April 1710

Birth near Aberdeen of Scottish philosopher Thomas Reid. A contemporary, and critic, of David Hume, he was one of the founders of the 'common sense' school of philosophy.

26 April 1711

David Hume, philosopher, historian, and one of the leading thinkers of the Scottish Enlightenment, was born in Edinburgh.

26 April 1812

German industrialist Alfred Krupp was born in Essen in the Ruhr area. Under his direction the Krupp company began producing ordnance; by the time of his death in 1887 the company had manufactured nearly 25,000 guns.

26 April 1889

Philosopher Ludwig Wittgenstein is born in Vienna into an immensely rich Austrian family. In his teens he will attend the same Linz school as Adolf Hitler.

26 April 1923

Lady Elizabeth Bowes-Lyon married Albert, Duke of York (later King George VI) in Westminster Abbey. Elizabeth laid her bouquet at the tomb of the Unknown Warrior in the abbey; other royal brides have subsequently sent their bouquets to be laid there.

26 April 1937: Guernica is battered by a three-hour bombing raid

Franco’s allies unleash hell on an unsuspecting Basque town

The afternoon of 26 April 1937 began like any other for the inhabitants of Guernica, a Basque town east of Bilbao. The weekly market was in full swing, with visiting shoppers swelling the town’s population to around 10,000 people. Soon, though, the peace was shattered when a fleet of bombers descended from the skies.

At 4.40pm, the first wave of bombers screamed into the airspace over the town. Over the course of that afternoon, dozens of German and Italian aircraft arrived, carpet-bombing the town and killing indiscriminately.

As well as obliterating houses, the bombers targeted the municipal water supply to prevent the townspeople from extinguishing the raging fires. The town’s residential buildings were largely constructed with timber, and the German aircraft carried incendiary bombs – clearly intending to create an inferno at a devastating level.

One eyewitness, a priest named Father Alberto Onaindía, described the horror as “diabolic”. He spoke of fires breaking out everywhere, and “defenceless inhabitants” running through the streets, taking cover under trees and inside houses as they were strafed by low-flying aircraft. The harassment continued into the evening until the aircraft flew away at about 7.45pm, leaving the town a smoking ruin.

Estimates of casualties vary widely, but judging by accounts from nearby hospitals that received the dead and injured following the attack, 1,645 people were killed and almost 900 more injured. And it is possible that the final death toll was even higher.

The ruthless attack on Guernica was intended as a sadistic show of support for General Francisco Franco’s Nationalists in the Spanish Civil War. The raid was masterminded by Colonel Wolfram von Richthofen, chief of staff of the Condor Legion –a Nazi unit sent to serve with the Nationalists.

Soon after the attack, Pablo Picasso created a piece that would become one of his most famous works of art. Guernica, a vast black-and-white painting depicting that fateful afternoon, became an iconic protest against war and all its horrors.

Despite public outcry, it was not until 1939, at the end of the Civil War, that the debris was finally cleared from the town. Today, the merciless attack on Guernica remains etched into Spain’s collective memory. | Written by Dominic Sandbrook

• Read more | Who was responsible for the bombing of Guernica?

26 April 1986: Chernobyl reactor explodes

A catastrophic nuclear accident starts in Ukraine

The Chernobyl disaster, which began on 26 April 1986, was the worst nuclear accident in history.Even now, its legacy continues to blight Belarus, Russia and Ukraine, the countries worst affected by the fallout. And although the Soviet authorities initially tried to cover it up, the accident dealt a hammer blow to their manicured image of socialist modernity.

The accident began during a routine test at Chernobyl nuclear power plant in Ukraine, scheduled for just after one o’clock in the morning of 26 April. Only moments after the test had started, reactor four suffered a huge and unexpected power surge.

What followed was the engineers’ worst nightmare: a rapid steam explosion, rupturing the fuel channels and severing the coolant lines. Seconds later, another explosion sent fragments of the nuclear core flying into the air, hurling more radioactive fallout over the surrounding area than had been released at Hiroshima. In less than a minute, the majority of the workers in the building had received fatal doses of radiation, though none of them knew it. Within three weeks, most of them were dead.

Local fire crews arrived only moments after the alarm sounded. One of the drivers, Grigorii Khmel, later recalled: “We arrived there at 10 or 15 minutes to two in the morning… We saw graphite scattered about. Misha asked: ‘Is that graphite?’ I kicked it away. But one of the fighters on the other truck picked it up. ‘It’s hot,’ he said.”

As Khmel admitted, none of the fire crews knew anything about radiation. “Even those who worked there had no idea. There was no water left in the trucks. Misha filled a cistern and we aimed the water at the top. Then those boys who died went up to the roof – Vashchik, Kolya and others, and Volodya Pravik … They went up the ladder… and I never saw them again.” | Written by Dominic Sandbrook

• Read more | Chernobyl: the story of a tragedy

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