What are the important events that happened on September 17? Here are historical events, facts, and some myths about this day.

September 17: Facts & Myths About This Day

September 17 is the 260^th day of the year 2025 in the Gregorian calendar. There are 105 days remaining until the end of this year. The day of the week is Wednesday.

Under the Julian calendar, this day is September 4, 2025 – a Wednesday. Both day of the week are the same but did you notice the difference with the Gregorian calendar?

When this day started, 1,758,067,200 seconds has elapsed since midnight of January 1, 1970 – the Unix epoch.

Strange as it may, if we name this day after a polygon then it will be called ‘dihectahexacontagon’ day.

Virgo is the zodiac sign of a person born on this day. Sapphire is the modern birthstone for this month. Agate is the mystical birthstone from Tibetan origin that dates back over a thousand years.

According to the lunisolar Chinese calendar, there are 153 days remaining before the start of the next Chinese New Year.

The ancient Maya civilization believes that the end of the world will happen on December 21, 2012. There are now 4,653 days since this fabled cataclysmic event.

September 17 Historical Events

• 1631 –
  Sweden wins a major victory at the Battle of Breitenfeld against the Holy Roman Empire during the Thirty Years War.
• 1776 –
  The Presidio of San Francisco is founded in New Spain.
• 1778 –
  The Treaty of Fort Pitt is signed. It is the first formal treaty between the United States and a Native American tribe (the Lenape or Delaware Indians).
• 1862 –
  American Civil War: The Allegheny Arsenal explosion results in the single largest civilian disaster during the war.
• 1928 –
  The Okeechobee Hurricane strikes southeastern Florida, killing upwards of 2,500 people. It is the third deadliest natural disaster in United States history, behind the Galveston Hurricane of 1900 and the 1906 San Francisco earthquake.
• 1941 –
  World War II: A decree of the Soviet State Committee of Defense, restoring Vsevobuch in the face of the Great Patriotic War, is issued
• 1974 –
  Bangladesh, Grenada and Guinea-Bissau join the United Nations.
• 1991 –
  Estonia, North Korea, South Korea, Latvia, Lithuania, the Marshall Islands and Micronesia join the United Nations.
• 1992 –
  An Iranian Kurdish leader and his two joiners are assassinated by political militants in Berlin, Germany.
• 2011 –
  Occupy Wall Street movement began in Zucotti Park, New York City.

Who were born on September 17?

• 1630 –
  Ranuccio II Farnese, Duke of Parma (d. 1694)
• 1839 –
  Ira Davenport, American magician (d. 1911)
• 1897 –
  Earl Webb, baseball player (d. 1965)
• 1907 –
  Warren Burger, 15th Chief Justice of the United States (d. 1995)
• 1928 –
  Roddy McDowall, English actor (d. 1998)
• 1934 –
  Maureen Connolly, American tennis player (d. 1969)
• 1945 –
  David Emerson, Canadian politician
• 1969 –
  Keith Flint, British musician (The Prodigy)
• 1972 –
  Brian Henry, American poet
• 1974 –
  Tormod Granheim, Norwegian adventurer

Who died on September 17?

• 1665 –
  Philip IV of Spain (b. 1605)
• 1762 –
  Francesco Geminiani, Italian violinist (b. 1687)
• 1771 –
  Tobias Smollett, Scottish novelist (b. 1721)
• 1803 –
  Franz Xaver Süssmayr, Austrian composer (b. 1766)
• 1858 –
  Dred Scott, American slave who unsuccessfully sued for citizenship (b. 1795)
• 1864 –
  Walter Savage Landor, English writer (b. 1775)
• 1908 –
  Thomas Selfridge, First Lieutenant in the U.S. Army (b. 1882)
• 1938 –
  Bruno Jasieński, Polish poet (b. 1901)
• 1948 –
  Folke Bernadotte, Swedish diplomat (b. 1895)
• 1994 –
  Karl Popper, Austrian philosopher (b. 1902)