Famous Days in September:  Most of these are official, some are not, but there are more days to celebrate than I ever knew.

1. 9/2:  VJ Day: End of WWII: There is some confusion over what date is V-J Day. You can consider any (or all) of three dates as V-J Day. President Harry S. Truman caused some of this confusion.  On August 14, 1945, the Japanese government cabled to the U.S. their surrender. This is the date of most modern observances.  On August 15, 1945, news of the surrender was announced to the world. This sparked spontaneous celebrations over the final ending of World War II.  On September 2, 1945, a formal surrender ceremony was held in Tokyo Bay aboard the USS Missouri. At the time, President Truman declared September 2 to be VJ Day.
2. 9/7:  Labor Day:  The first Labor Day was held celebrated in New York City on September 5, 1882 and was started by the Central Labor Union in New York City. In 1884, it was moved to the first Monday in September where it is celebrated today. Labor Day quickly became popular and one state after another voted it as a holiday. On June 28, 1894, the U.S. congress voted it a national holiday.
3. 9/13:  Grandparent’s Day:  National Grandparent's Day originated in 1978. Then President Jimmy Carter declared it to be the first Sunday after Labor Day.
4. 9/13:  Uncle Sam Day:  The officially recognized theory dates back to soldiers stationed near Troy, New York during the war of 1812. Barrels of meat they received were stamped "U.S." The supplier was Samuel Wilson of Troy, New York. Solders jokingly referred to him as "Uncle Sam". In 1813, the first image of "Uncle Sam" appeared. In 1961, the U.S. Congress issued a resolution recognizing "Uncle Sam" Wilson, and authorizing a monument in his hometown in Troy, NY.  Uncle Sam Day became official in 1989, when a joint resolution of Congress designated September 13 "Uncle Sam Day".  This date was selected, as "Uncle Sam" Wilson was born on September 13, 1776.
5. 9/16:  American Legion Day: The American Legion was granted its federal charter by Congress on this day in 1919. It was established to support and assist veterans returning from World War I. Since then it has grown and supported veterans of all wars, and veterans of peacetime as well.  While the American Legion was formed in 1919, it wasn't until 2009 that this special day was created. On September 15, 2009, Congress proclaimed September 16 as American Legion Day.
6. 9/16:  Mayflower Day:  Not official, but Mayflower Day celebrates the date the Mayflower sailed from Plymouth, England to America. On September 16, 1620, 102 men, women, and children set sail from Plymouth, England. Their destination was the New World, where they could have religious freedom, and continue using their native language, culture, and customs.
7. 9/17:  Citizenship Day: On February 29, 1952, President Harry Truman signed a bill establishing Citizenship Day on September 17 of each year. The roots of this holiday go back to I Am an American Day, which was established in 1940 by Congress as the third Sunday in May. This day was moved and renamed to Citizenship Day to coincide with the signing of the U.S. Constitution on September 17, 1787.
8. 9/17:  Constitution Day:  Yep, the signing of our Constitution:  The Constitutional Congress of the United States of America held it's final meeting on September 17, 1787. Do you have any idea why? That's right! It was to sign the Constitution of the United States of America, a document for which they so painstakingly labored to create and perfect.  After the meeting there was still much to do. Individual states then had to meet and vote on it. The U.S. Constitution did not go into effect until  two years later on March 4, 1789.
9. 9/22:  Autumn Equinox Day:  Beginning of Fall
10. 9/26:  Johnny Appleseed Day:  It’s not an official holiday, but Johnny Appleseed Day honors one of America's great legends. Johnny Appleseed was a real person. Born John Chapman, he was among the American settlers who were captivated by the movement west across the continent. As Johnny Appleseed travelled west, he sold apple trees and seeds to settlers, and planted many apple trees himself along the way. Johnny Appleseed continued planting and selling apple trees for over forty years. With every apple tree that was planted, the legend grew.
11. 9/27:  National Hunting & Fishing Day:  Hunters and fishermen were early supporters of conservation and wildlife management. It goes back to over one hundred years, and was led by President Theodore Roosevelt, an avid sportsman. They urged sustainable fish and game management. During this time, the first hunting and fishing licenses were required.  Ira Joffe of Upper Darby, PA was the first to suggest and promote a day of thanks to sportsmen for their conservation efforts. In 1970, thanks in part to his efforts, 1970 Pennsylvania declared the first "Outdoor Sportsman Day”.  Then, in June, 1971, U.S. Senator Thomas McIntyre of New Hampshire, introduced Joint Resolution 117 authorizing every 4th Saturday in September to be National Hunting and Fishing Day (NHFD) .  In May, 1972, President Richard Nixon issued a proclamation for NHFD. He said "I urge all citizens to join with outdoor sportsman in the wise use of our natural resources, and in insuring their proper management for the benefit of future generations."
12. 9/28:  National Good Neighbor’s Day:  In 2003, the U.S. Senate passed a resolution, sponsored by Montana Senator Max Baucus, making September 28, National Good Neighbor Day. Previously, this day was celebrated on the fourth Sunday of September.