International Patient Safety Day: This day is observed to raise awareness about the importance of patient safety and to promote measures for ensuring patient safety in healthcare systems.
World Clean-up Day: This day is observed to raise awareness about waste management and to encourage communities to clean up their surroundings.
International Country Music Day: This day celebrates the music genre of country music and its contributions to music culture around the world.
International Day for the Preservation of the Ozone Layer: This day is observed to raise awareness about the depletion of the ozone layer and promote measures for its protection.
Constitution Day (United States): This day commemorates the adoption of the United States Constitution and honors the country’s history and democracy.
1787: The United States Constitution is signed by the delegates of the Constitutional Convention in Philadelphia, Pennsylvania.
1862: The Battle of Antietam, the bloodiest day of the American Civil War, takes place in Maryland.
1908: The Wright brothers demonstrate their aircraft, the Wright Flyer, to the U.S. Army at Fort Myer, Virginia.
1939: The Soviet Union invades Poland from the east, two weeks after Germany invaded from the west, marking the start of World War II.
1978: The Camp David Accords are signed by Israeli Prime Minister Menachem Begin and Egyptian President Anwar Sadat, with U.S. President Jimmy Carter mediating.
2011: Occupy Wall Street, a protest movement against economic inequality and corporate influence in politics, begins in Zuccotti Park in New York City.