Edward Jenner administers the first smallpox inoculation.

Edward Jenner, often hailed as the father of immunology, made a groundbreaking contribution to medicine in the late 18th century by developing the first successful smallpox vaccine. At the time, smallpox was one of the deadliest diseases, killing millions worldwide. Jenner noticed that milkmaids who had contracted cowpox—a much milder disease—seemed immune to smallpox. In 1796, he tested this observation by inoculating a young boy, James Phipps, with pus from a cowpox sore. Later, when exposed to smallpox, the boy showed no signs of illness. This experiment laid the foundation for modern vaccination. Jenner’s work not only demonstrated that deliberate exposure to a less dangerous virus could confer protection against a deadly one, but it also initiated the eventual global eradication of smallpox by the World Health Organization in 1980—a monumental achievement in public health.

Germany’s conquest of France begins, as the German army crosses the Meuse. Winston Churchill makes his “blood, toil, tears, and sweat” speech to the House of Commons.

Winston Churchill’s “Blood, Toil, Tears, and Sweat” speech, delivered on May 13, 1940, marked his first address to the House of Commons as Prime Minister during one of the darkest periods of World War II. The phrase itself—“I have nothing to offer but blood, toil, tears, and sweat”—has become iconic, encapsulating Churchill’s stark realism and unflinching resolve. In the speech, he didn’t sugarcoat the severity of the situation; instead, he rallied Parliament and the British public with a call for unity, sacrifice, and unwavering determination in the face of Nazi aggression. The speech emphasized that victory at all costs was the only acceptable outcome, and it laid the emotional and moral groundwork for Britain’s resistance. Churchill’s rhetoric was both sobering and galvanizing, combining grim honesty with an undercurrent of defiant hope—a hallmark of his wartime leadership style.

Napoleon Bonaparte conquers Venice.

Napoleon Bonaparte was a French military leader and emperor who rose to prominence during the French Revolution and dominated European affairs in the early 19th century. Born in Corsica in 1769, he rapidly advanced through military ranks due to his strategic brilliance and charismatic leadership. In 1799, he seized political power in a coup d’état, eventually declaring himself Emperor of the French in 1804. Napoleon is best known for his ambitious campaigns across Europe—most notably the Napoleonic Wars—through which he built a vast empire that stretched from Spain to Russia. However, his aggressive expansionism led to massive resistance and ultimately his downfall, especially after the disastrous invasion of Russia in 1812. He was exiled to Elba, made a dramatic return for the Hundred Days, but was finally defeated at the Battle of Waterloo in 1815 and exiled again to the remote island of Saint Helena, where he died in 1821. His legacy is complex—seen both as a military genius and a power-hungry ruler—but his reforms, especially the Napoleonic Code, had lasting impacts on legal systems across Europe.

Klaus Barbie goes on trial in Lyon for war crimes committed during World War II.

Klaus Barbie, infamously known as the “Butcher of Lyon,” was a German SS officer during World War II who gained notoriety for his brutal actions as the head of the Gestapo in Lyon, France. Born in 1913, Barbie oversaw the arrest, torture, and deportation of hundreds of resistance fighters and Jews. One of his most heinous acts was the capture and murder of Jean Moulin, a key figure in the French Resistance. After the war, he escaped justice by fleeing to South America with the help of U.S. intelligence services, who utilized him for anti-communist operations during the early Cold War. He lived in Bolivia under the alias Klaus Altmann until his extradition to France in 1983. In 1987, Barbie was tried and convicted of crimes against humanity and sentenced to life in prison, where he died in 1991. His story remains a chilling reminder of the long reach of Nazi atrocities and the complicated post-war politics that allowed some war criminals to evade justice for decades.

In Germany, the Nazis stage massive public book burnings.

The Nazi public book burnings, most infamously on May 10, 1933, were a series of coordinated events across Germany where thousands of books deemed “un-German” were ceremonially burned in public squares. These events were driven by the Nazi regime’s desire to control ideology and culture, targeting works by Jewish, Marxist, pacifist, and liberal authors—names like Karl Marx, Sigmund Freud, Erich Maria Remarque, and Helen Keller were among those purged. Orchestrated mainly by the German Student Union and supported by high-ranking Nazi officials like Joseph Goebbels, the burnings were symbolic acts of censorship and cultural cleansing, aimed at eliminating dissenting voices and establishing a homogenous national identity aligned with Nazi ideology. These spectacles were not just about destroying books—they were about consolidating power through the erasure of intellectual diversity and reinforcing Nazi propaganda through fear and public conformity.

The figure who later became Mr. Punch makes his first recorded appearance in England

The Punch and Judy show is a traditional British puppet performance that dates back to the 17th century, rooted in the Italian commedia dell’arte. The central character, Mr. Punch, is instantly recognizable by his hooked nose, hunched back, and shrill, squawking voice—created with a special device called a swazzle. The plot usually involves a chaotic series of slapstick encounters between Punch and various figures like his wife Judy, a baby, a policeman, a crocodile, and sometimes even the Devil. What makes the show iconic is its dark, exaggerated humor and satirical take on authority and domestic life, often delivered through outrageous violence played for laughs. Though modern sensibilities have led to some revisions in content, Punch and Judy still survives today—mainly at British seaside towns and festivals—as a quirky cultural artifact and a relic of anarchic street theatre.

The Irish Literary Theatre in Dublin produced its first play.

The Irish Literary Theatre, founded in 1899 in Dublin, was a pivotal initiative in the Irish Literary Revival, aiming to create a national theatre that would reflect Irish identity through serious drama. Spearheaded by W. B. Yeats, Lady Gregory, Edward Martyn, and later George Moore, the theatre was envisioned as a platform for plays rooted in Irish themes, myths, and language, rather than the popular melodramas of the time. Its first production, The Countess Cathleen by Yeats, stirred both praise and controversy, setting the tone for a bold cultural movement. Although the original Irish Literary Theatre only operated until 1901 due to financial and organizational struggles, it laid the groundwork for the Abbey Theatre, which became Ireland’s national theatre in 1904. This short-lived but influential venture helped crystallize the idea of theatre as a cultural and political tool during a period of growing Irish nationalism.

Greece’s independence is recognized by the Treaty of London.

The independence of Greece was formally recognized through the Treaty of London, signed on July 6, 1827, by Great Britain, France, and Russia. This treaty marked a pivotal moment in the Greek War of Independence (1821–1829), during which the Greeks revolted against Ottoman rule. Although initially these powers aimed to establish Greek autonomy under Ottoman suzerainty, the situation evolved following the Battle of Navarino later that year, where the allied fleet decisively defeated the Ottoman-Egyptian navy. This shift in military balance increased diplomatic pressure on the Ottoman Empire. Ultimately, Greek independence was fully acknowledged by the Treaty of Constantinople in 1832, but the 1827 Treaty of London laid the diplomatic groundwork by legitimizing European intervention and signaling international support for the Greek cause.

The Russian Constitution of 1906 is adopted (on April 23 by the Julian calendar).

The Russian Constitution of 1906, officially titled the Fundamental Laws of the Russian Empire, marked a significant—though limited—step toward constitutional monarchy in Tsarist Russia. Issued by Tsar Nicholas II on April 23, 1906, just days before the opening of the first State Duma, it was both a response to the 1905 Revolution and an attempt to appease growing public unrest without fully surrendering autocratic power. While it formally introduced a bicameral legislature—the State Council (partly appointed) and the State Duma (elected)—real power remained firmly in the Tsar’s hands. He retained authority over foreign policy, the military, the Orthodox Church, and could dissolve the Duma at will. The constitution also enshrined certain civil liberties, such as freedom of speech and assembly, but these were often undermined in practice by repressive laws and police powers. In essence, the 1906 Constitution was more about preserving imperial control under the guise of reform than genuinely distributing power, setting the stage for continued instability in the lead-up to the 1917 revolutions.