Clean up Your Room Day
National Train Day
Confederate Memorial Day, a state holiday in both North and South Carolina, honoring the memory of the Confederate soldiers and civilians lost during the Civil War. North and South Carolina, mark the anniversaries of the death of Thomas Jonathan ‘Stonewall’ Jackson (a general in the Confederate army) in 1863 and the capture of Jefferson Davis in 1865.
On May 10, 1503, Christopher Columbus visited the Cayman Islands and named them Las Tortugas after the numerous turtles there.
Jacques Cartier visited Newfoundland in 1534.
The Parliament of Great Britain passed the Tea Act, on May 10, 1773. It is designed to save the British East India Company by granting it a monopoly on the North American tea trade.
Louis XVI and Marie Antoinette became King and Queen of France on May 10, 1774. They were executed in 1793.
In 1775, representatives from the Thirteen Colonies began the Second Continental Congress in Philadelphia.
Fort Ticonderoga Day, observed at Ticonderoga, New York, marking the capture of the fort by Ethan Allen and the Green Mountain Boys in 1775
May 10, 1797, the First Navy ship, the “USS United States,” is launched
First Barbary War: The Barbary pirates of Tripoli declared war on the United States of America on May 10, 1801.
The First Transcontinental Railroad, linking the eastern and western United States, was completed at Promontory Summit, Utah (not Promontory Point) with the golden spike in 1869.
Victoria Woodhull became the first woman nominated for President of the United States in 1872.
In 1893 the Supreme Court of the United States ruled in Nix v. Hedden that a tomato is a vegetable, not a fruit, under the Tariff Act of 1883.
J. Edgar Hoover is appointed the Director of the United States’ Federal Bureau of Investigation on May 10, 1940, and remains so until his death in 1972.
May 10, 1940 – Winston Churchill became Prime Minister of the United Kingdom on the same day that Germany invaded the Netherlands, Belgium and Luxembourg.
Bill Haley & His Comets release “Rock Around the Clock” in 1954. It is the first rock and roll record to reach number one on the Billboard charts.
The first newspaper cartoon in America was created by Benjamin Franklin and published in his “Pennsylvania Gazette” on May 9, 1754. It showed a divided snake with the caption: “Join or Die”. Each segment represented one colony or region.
Jim Gentile of the Baltimore Orioles became the first player in baseball history to hit grand slams in consecutive innings on May 9, 1961.
Watergate Scandal: The United States House of Representatives Judiciary Committee opened formal and public impeachment hearings against 
Birthday of 
George Eastman patents “Kodak box camera” in 1888.
1904 – “Flexible Flyer” trademark registered.
1536 – King Henry VIII of England ordered English-language Bibles be placed in every church.
1682 – Louis XIV of France moved his court to the Palace of Versailles.
Birthday of Sigmund Freud (May 6, 1856), Austrian physician, founder of psychoanalysis.
1889 – The Eiffel Tower was officially opened to the public at the Universal Exposition in Paris.
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Hindenburg disaster: On May 6, 1937, the German Zeppelin Hindenburg catches fire and is destroyed within a minute while attempting to dock at Lakehurst, New Jersey. Thirty-six people were killed. Interesting reading at 
Birthday of Karl Marx (1818) , German philosopher, economist, historian, sociologist, political theorist, journalist and socialist revolutionary, author of “Das Kapital” and The Communist Manifesto, available at 
The Music Hall in New York City (later known as Carnegie Hall) has its grand opening and first public performance on May 5, 1891, with Tchaikovsky as the guest conductor.
On May 5, 1973, Secretariat won the 1973 Kentucky Derby in 1:59 2/5, a still standing record. He went on to win the Preakness Stakes and the Belmont Stakes, the first U.S. Triple Crown winner in 25 years. He set records in all three events.
Emperor Napoleon I of France arrived at Portoferraio on the island of Elba on May 4, 1814 to begin his exile.
May 4, 1979 – Margaret Thatcher became the first female Prime Minister of the United Kingdom.
Birthday of Niccoló Machiavelli (May 3, 1469), Italian statesman and author of “The Prince”
In part because of the poem’s popularity, the poppy was adopted as the Flower of Remembrance for the war dead of Britain, France, the United States, Canada and other Commonwealth countries.
The 108-story Sears Tower (now named the Willis Tower) in Chicago is topped out at 1,451 feet as the world’s tallest building in 1973.
1840 – The Penny Black, the first official adhesive postage stamp, was issued in the United Kingdom.
1915 – The RMS Lusitania departed from New York City on her two hundred and second, and final, crossing of the North Atlantic. Six days later, the ship was torpedoed off the coast of Ireland with the loss of 1,198 lives, including 128 Americans, rousing American sentiment against Germany.