Events
- 1806 – Andrew Jackson kills Charles Dickinson in a duel after the man had accused Jackson's wife of bigamy.
- 1854 – The Kansas–Nebraska Act becomes law establishing the US territories of Nebraska and Kansas.
- 1868 – Decoration Day (the predecessor of the modern "Memorial Day") observed in the United States for the first time (By "Commander–in–chief of the Grand Army of the Republic" John A. Logan's proclamation on May 5).
- 1879 – New York City's Gilmores Garden is renamed Madison Square Garden by William Henry Vanderbilt and is opened to the public at 26th Street and Madison Avenue.
- 1879 – An F4 tornado strikes Irving, Kansas, killing 18 and injuring 60.
- 1883 – In New York City, a rumor that the Brooklyn Bridge is going to collapse causes a stampede which crushes twelve people.
- 1911 – At the Indianapolis Motor Speedway, the first Indianapolis 500 ends with Ray Harroun becoming the first winner of the 500–mile auto race in his Marmon Wasp.
- 1914 – New & then-largest Cunard ocean liner RMS Aquitania, 45,647 tons, sails on her maiden voyage from Liverpool, England, to New York City.
- 1922 – In Washington, D.C., the Lincoln Memorial is dedicated.
- 1948 – A dike along the flooding Columbia River breaks, obliterating Vanport, Oregon within minutes. Fifteen people die and tens of thousands are left homeless.
- 1958 – Memorial Day: The remains of two unidentified American servicemen, killed in action during World War II and the Korean War, are buried at the Tomb of the Unknowns in Arlington National Cemetery.
- 1967 – At the Ascot Park in Gardena, California, daredevil Evel Knievel jumps his motorcycle over 16 cars lined–up in a row.