|Holiday name||Holiday location||Holiday type|
|World Day for Cultural Diversity for Dialogue and Development||-||International (Culture & History, United Nations)|
|Navy Day||Chile||National Holiday|
|Independence Day||Montenegro||National Holiday|
|Talk Like Yoda Day||-||Unofficial (Art & Entertainment, Weird & Obscure)|
|Saint Helena's Day||Saint Helena||Public Holiday|
|National American Red Cross Founder’s Day||-||Unofficial (Appreciation & Honor)|
|National Waitstaff Day||-||Unofficial (Work & Occupation)|
|National Strawberries and Cream Day||-||Unofficial (Food & Drinks)|
|National Memo Day||-||Unofficial (Lifestyle, Work & Occupation)|
|National Learn to Swim Day||-||Unofficial (Activity & Action)|
|Armed Forces Day||United States||Observance|
Historical Events on May 21
- 1851: In the country of Columbia – in South America – slavery is abolished on this day.
- 1856: The Siege Of Lawrence occurs on this day when a pro-slavery posse captures and ransacks the city of Lawrence in Kansas.
- 1863: The Union Army finishes blocking off all escape routes out of Hudson, Louisiana during the American Civil War.
- 1864: During the American Civil War, the Battle of Spotsylvania ends on this day.
- 1871: The Paris Commune is invaded by French forces and street-to-street fighting breaks out. By the end of the week – a week that’s since been dubbed Bloody Week – over twenty thousand Communards were killed and almost forty thousand were arrested.
- 1881: Clara Barton starts the American Red Cross in Washington, D.C.
- 1917: The Great Atlanta Fire of 1917 rages across the city of Atlanta, Georgia. It destroys over two thousand homes, churches and businesses and it displaces over ten thousand people. Total cost of the fire’s damages totaled over five million dollars.
- 1927: Charles Lindbergh finishes the world’s first non-stop solo flight over the Atlantic Ocean when he touched down in Paris at Bourget Field.
- 1932: Due to inclement weather, Amelia Earhart has to land in a pasture in Derry, Ireland – thereby becoming the first woman to fly over the Atlantic Ocean alone.
- 1946: Louis Slotin is accidentally irradiated during an experiment with the core at Los Alamos National Laboratory.
- 1961: In order to restore order after race riots broke out, Alabama Governor John Malcolm Patterson declares Martial Law.
Famous Birthdays on May 21
- English poet, translator and essayist, Alexander Pope is born in 1688.
- English philanthropist Elizabeth Fry is born in 1780.
- English paleontologist Mary Anning is born in 1799.
- American actor and director, Robert Montgomery is born in 1904.
- American singer-songwriter Fats Waller is born in 1904.
- American singer and actor, Dennis Day is born in 1918.
- Russian physicist and Nobel Prize laureate, Andrei Sakharov is born in 1921.
- English bass player John Dalton is born in 1943.
- English songwriter and guitarist, Hilton Valentine is born in 1943.
- American actor and writer, Richard Hatch is born in 1945.
- American comedian, actor, writer and U.S Senator, Al Franken is born in 1951.
- American bodyguard, wrestler and actor, Mr. T is born in 1952.