No birth certificate survives for William Shakespeare, only a parish register entry recording his baptism on April 26, 1564. Tradition, and a certain poetic tidiness, fixed his birthday at April 23 — the same date on which he would die 52 years later in 1616. Scholars treat the date as probable rather than proven.

Sir Francis Drake, the Elizabethan privateer who had circumnavigated the globe and helped defeat the Spanish Armada, died of dysentery off Portobelo, Panama, during an unsuccessful final expedition against Spanish American ports. He was buried at sea in a lead coffin, which has never been found despite repeated searches.

Cervantes died on April 22 by his own reckoning but was buried on April 23, and due to Spain's earlier adoption of the Gregorian calendar, his death actually preceded Shakespeare's by ten days despite sharing a calendar date. The coincidence still anchors UNESCO's World Book and Copyright Day, celebrated globally on April 23.

In the chaotic weeks following the bombardment of Fort Sumter, Louisiana's state militia mobilized to defend New Orleans and control traffic on the Mississippi River, a strategic artery both the Union and Confederacy recognized as vital. The city, the Confederacy's largest, would fall to Union forces just over a year later in April 1862.

Adolphus Busch, working with his father-in-law Eberhard Anheuser's brewery in St. Louis, introduced Budweiser as a pasteurized, bottled lager designed to survive shipping across the country. Named after the Bohemian town of Budweis, it used pasteurization technology borrowed from Louis Pasteur to give it a shelf life rival beers lacked.

Meeting at the Cosmos Club in Washington, D.C., 33 men founded the National Geographic Society "for the increase and diffusion of geographical knowledge." The organization would go on to sponsor expeditions to both poles, the deepest ocean trenches, and outer space, and its magazine's iconic yellow border became one of the most recognized designs in publishing.

In the wake of the April 12 Shanghai Massacre, in which Chiang Kai-shek's Nationalist forces turned violently on their Communist allies, the Wuhan-based leftist Kuomintang government formally condemned Chiang's actions in late April 1927, cementing the rupture between Nationalists and Communists that would fuel decades of civil war in China.

RCA began selling the CT-100, the first mass-produced color television, at a price of about $1,000 in 1954 — equivalent to over $11,000 today. Few Americans could afford it, and color broadcasts remained scarce for years, but it marked the opening shot in a technology race that would eventually put color TVs in nearly every home.

Amid the broader détente of the early 1970s, American and Soviet space officials finalized plans for a joint mission that would dock an Apollo spacecraft with a Soyuz capsule in orbit — a symbolic thaw after over a decade of fierce space race rivalry. The mission itself flew in July 1975, when astronauts and cosmonauts shook hands 140 miles above the Earth.