- The first American went into space. (1961) Alan Bartlett Shepard, Jr. became the first American in space on this day when he was launched into orbit inside the Freedom 7 space capsule. It was just less a month after the first person ever went into space — Cosmonaut Yuri Gagarin, from the USSR.
- The first patent was granted to a woman in the US. (1809) Mary Dixon Kies was granted a patent for a method of making hats by weaving straw together with silk and thread.
- Mexican forces defeated the French in an event later celebrated as the Cinco de Mayo. (1862) It was a huge victory for Mexico in the Mexican-French War, and was one of the first real signs that the country could defend itself against larger foreign powers. The day is now celebrated as a national holiday in Mexico.
- The first train robbery took place in the US. (1865) The details are sketchy on the North Bend robbery, the first train robbery in the US, because of biased newspaper reports at the time. Depending on the newspaper, the crime is said to have been committed by guerrilla Confederate soldiers out of work since the war ended about a month earlier or simply random criminals. The robbers got away with more than $1,000 US Dollars (USD) in cash, as well as valuables from the passengers.
- Carnegie Hall opened. (1891) It was originally known as the Music Hall in New York City, and had its first public performance on this day, with the Russian composer Peter Tchaikovsky as a special guest conductor.
- Spider-Man grossed more than $100 million USD in its opening weekend. (2002) It was the first movie to gross so highly in the first weekend, and held that record until The Dark Knight broke it in 2008.
- The first "perfect" baseball game was thrown. (1904) The first perfect game — called so if no players reach a base during nine innings of play — was pitched by Cy Young on this day.
- West Germany gained full sovereignty. (1955) The country had been occupied by Allied forces since the end of World War II just as East Germany was occupied by USSR forces. The country remained sovereign until the two sides of Germany reunited in 1990.
- John Scopes was arrested for teaching the theory of evolution. (1925) Scopes' trial, known as the Scopes Monkey Trial, was extremely highly publicized, and though Scopes lost, the verdict was overturned on a technicality. After the trial, many science programs expanded to include the theory of evolution in their curricula.
- Napoleon died. (1821) The former Emperor of France died in exile and was buried on St. Helena, where he had been sent after first escaping from exile on the island of Elba. Due to a dispute about which of his titles should be on his tombstone, his grave was left blank until his remains were repatriated to France.