September 17 has seen constitutions signed, battles fought, and moments that defined American democracy.
Delegates to the Constitutional Convention in Philadelphia signed the United States Constitution, creating the framework for American government. The document established the world's oldest written national constitution still in force.
The bloodiest single day in American history saw over 22,000 casualties at Antietam Creek in Maryland. The strategic Union victory gave Lincoln the confidence to issue the Emancipation Proclamation.
President Carter brokered a peace agreement between Israeli Prime Minister Begin and Egyptian President Sadat. The accords led to the first peace treaty between Israel and an Arab nation.
Puritan colonists led by John Winthrop founded the city of Boston, which would become a center of American education, culture, and revolutionary activity. Winthrop described their community as 'a city upon a hill.'
The largest airborne operation in history launched in the Netherlands, attempting to capture bridges and end the war by Christmas. The operation ultimately failed at Arnhem, the 'bridge too far.'
Protesters occupied Zuccotti Park in New York City's financial district, launching the Occupy movement. The protest against economic inequality and the power of the '1%' spread to cities worldwide.
Dutch scientist Leeuwenhoek wrote a letter describing 'animalcules' he observed through his microscopes, the first known description of bacteria. His observations opened the field of microbiology.