Seventeen-year-old Joan of Arc entered Orléans at nightfall, having convinced the dauphin Charles to let her join the relief effort against the English siege that had gripped the city for months. Her arrival, amid a cheering crowd bearing torches, galvanized French morale. Within days, French forces broke the siege entirely, turning the tide of the Hundred Years' War and beginning Joan's meteoric rise from peasant visionary to national icon.

After decades of expansion transforming a modest hunting lodge into an immense palace complex, Louis XIV moved his court and government permanently to Versailles. The relocation centralized French political power around the king's person, forced nobility into costly courtly life, and produced one of history's most influential architectural and landscape achievements, copied by monarchies across Europe for the next two centuries.

Though formally dated April 30, 1803, the Louisiana Purchase negotiations concluded in the final days of April, with American envoys Robert Livingston and James Monroe securing France's vast Louisiana Territory for roughly $15 million. The deal, struck with Napoleon Bonaparte's government, doubled the size of the United States overnight and opened the way for westward expansion across the continent.

Duke Ellington, born in Washington D.C. to a family that encouraged his early piano lessons, went on to lead his orchestra for nearly fifty years, composing over a thousand pieces and helping elevate jazz to a serious art form. From the Cotton Club residency of the late 1920s to symphonic suites and sacred concerts late in his career, Ellington's genius for orchestral color and collaborative composition with musicians like Billy Strayhorn reshaped American music.

Hirohito was born into the Chrysanthemum Throne's long lineage, destined to become Japan's 124th emperor in 1926. His 62-year reign would span the militarist expansion of the 1930s, World War II, the atomic bombings, and Japan's postwar transformation into a pacifist economic power. April 29 was celebrated in Japan as his birthday holiday, later renamed Showa Day.

Soldiers of the U.S. 45th and 42nd Infantry Divisions liberated Dachau, the first Nazi concentration camp, established in 1933 near Munich. They found more than 30,000 starving survivors and boxcars packed with corpses. Some American soldiers, overwhelmed by what they witnessed, summarily executed captured German guards—an incident later investigated by the Army. Dachau became a defining symbol of the Holocaust's horror for the liberating Allied forces.

Building on Jack Kilby's original 1958 integrated circuit breakthrough, engineering teams throughout the mid-1960s pushed forward refinements in chip miniaturization and manufacturing that would soon enable calculators, computers, and eventually consumer electronics to shrink dramatically in size and cost, setting the stage for the microprocessor era to follow within a decade.

With Armed Forces Radio broadcasting Bing Crosby's 'White Christmas' as a covert signal, American forces launched Operation Frequent Wind, evacuating over 7,000 Americans and South Vietnamese from Saigon by helicopter as the city fell to North Vietnamese troops. Desperate crowds stormed the U.S. Embassy compound. Helicopters were dumped overboard from carriers to make room for more flights, one of the war's most searing final images.

Prince William, second in line to the British throne, married Catherine Middleton at Westminster Abbey in a ceremony blending centuries-old royal tradition with modern global media spectacle. An estimated global television audience in the hundreds of millions to two billion watched, while over a million people lined the streets of London. The couple were immediately created the Duke and Duchess of Cambridge.