May 21

May 21 is the 142nd day of the year, and the American record for it runs from 1660 to 2024 — a span of 364 years. The entry that anchors it: American Civil War, 1863.

The earliest entries here predate the republic entirely. In 1660, the Battle of Long Sault concludes after five days in which French colonial militia, with their Huron and Algonquin allies, are defeated by the Iroquois Confederacy.

The antebellum decades brought the date closer to the country’s central argument. In 1863, American Civil War — the Union Army succeeds in closing off the last escape route from Port Hudson, Louisiana, in preparation for the coming siege. A year later, in 1864, American Civil War — the inconclusive Battle of Spotsylvania Court House in Virginia ended with combined Union and Confederate casualties totaling around 31,000.

The early twentieth century brought industry, air travel and war to the date. In 1934, Oskaloosa, Iowa, becomes the first municipality in the United States to fingerprint all of its citizens.

After 1945 the date reflects a country operating at global scale. In 1946, while working with a mass of plutonium known as the demon core, Manhattan Project physicist Louis Slotin accidentally exposed himself to a lethal dose of hard radiation, making him the second victim of a criticality accident in history. Then, in 1961, American civil rights movement — Alabama Governor John Malcolm Patterson declares martial law in an attempt to restore order after race riots break out.

The most recent entries fall within living memory. In 2005, the world's tallest roller coaster, Kingda Ka, opened at Six Flags Great Adventure in Jackson, New Jersey, U.S. Then, in 2024, the Greenfield tornado kills five and injures 35 across rural Iowa, United States. Wind speeds in excess of 480 kilometres per hour (300 mph) are estimated from measurements for the third time in history.

The date is also a birthday. Among the Americans born on May 21: Alfred Moore (1755), American lawyer and judge; William P. Sprague (1827), American banker and politician; Ella Stewart Udall (1855), American telegraphist; Anne Walter Fearn (1867), American physician; and Glenn Curtiss (1878), American cyclist and engineer.

May 21 is also a date of endings. Among the Americans who died on it: Hernando de Soto (1542), Spanish-American explorer; John Eliot (1690), English-American minister and missionary; John Drew (1862), Irish-American actor and manager; and Williamina Fleming (1911), Scottish-American astronomer and academic.

The record for May 21 runs 364 years deep across 8 entries. Read in sequence, the date stops being a coincidence and starts being a through-line.