July 18

July 18 is the 200th day of the year, and the American record for it runs from 1863 to 2013 — a span of 150 years. The entry that anchors it: American Civil War, 1863.

By the middle of the nineteenth century the date carries heavier freight. In 1863, American Civil War — Led by Colonel Robert Gould Shaw, the 54th Massachusetts Infantry Regiment, one of the first African-American military units in the Union Army, spearheaded an assault on Fort Wagner, South Carolina.

In the postwar nineteenth century the date tracks a nation rebuilding. In 1899, Newsboys from Long Island City turned over a distribution wagon for the New York Journal, marking the start of the Newsboys' strike of 1899.

In the first half of the twentieth century the date turns technological. In 1914, the U.S. Congress forms the Aviation Section, U.S. Signal Corps, giving official status to aircraft within the U.S. Army for the first time.

The postwar entries show a nation both expanding and contesting itself. In 1949, Francisco Javier Arana, the chief of the Guatemalan armed forces, was killed in a shootout with supporters of President Juan José Arévalo. Then, in 1966, Angered by racism and poverty, African American residents of the Hough neighborhood of Cleveland began to riot for six days. Then, in 1984, a gunman massacred 21 people and injured 15 others at a McDonald's restaurant in the district of San Ysidro of San Diego, California. Five years on, in 1989, American actress Rebecca Schaeffer was shot and killed by Robert John Bardo, eventually prompting the passage of anti-stalking laws in California.

Closer to the present, the date is still accumulating. In 2013, the Government of Detroit, with up to $20 billion in debt, files for the largest municipal bankruptcy in U.S. history.

The date is also a birthday. Among the Americans born on July 18: Virgil Earp (1843), American marshal; Margaret Brown (1867), American philanthropist and activist; Larry McLean (1881), Canadian-American baseball player; Simon Bolivar Buckner Jr. (1886), American general; and Olga Spessivtseva (1895), Russian-American ballerina.

July 18 is also a date of endings. Among the Americans who died on it: John Paul Jones (1792), Scottish-American admiral and diplomat; Robert Gould Shaw (1863), American colonel; Horatio Alger (1899), American novelist and journalist; and Benjamin C. Truman (1916), American journalist and author.

The date carries formal observance as well — Nelson Mandela International Day. July 18 carries 8 entries spread across 150 years. None of the people in them knew they were sharing a date; that is a pattern only visible looking back.