By Katie Lange

The Fourth of July makes us think of a lot of things: Barbeques. Parades. Fireworks. Supporting America’s troops. Lots of red, white and blue. Will Smith’s movie “Independence Day.”

Oh yeah, and the freedom that our founding fathers declared to the world over 200 years ago.

On that day years ago, 56 patriots pledged their lives and honor to defend America’s rights to life, liberty and the pursuit of happiness – a sentiment our current troops still live by.

A boy wears American flag garb on a float in a Fourth of July parade in Vale, Oregon, in 1941. | Photo credit Courtesy Library of Congress

While the date July 4, 1776 is ingrained in most of our memories, here are some cool facts you may not know about the holiday:

1. Unofficially, the United States’ Independence Day is July 2 — when the Second Continental Congress made the unanimous decision to break from England.

However, the actual Declaration of Independence wasn’t approved and adopted until July 4, when the Liberty Bell was rung in Philadelphia. The document also didn’t become official until Aug. 2, 1776, when most congressional delegates finally signed it.

2. It’s often thought that July 4 kicked off the fight for independence, but the Revolutionary War actually began more than a year before that on April 19, 1775, when the first shots were fired at Lexington and Concord in Massachusetts.

That was one day after the legendary ride of Paul Revere.

3. John Adams and Thomas Jefferson — both signers of the Declaration of Independence who later became president — died on July 4, 1826, within hours of each other.
4. On July 4, 1776, there were an estimated 2.5 million people living in America. On July 2, 2018, there were about 328 million, according to the U.S. Census Bureau.
5. Americans today avidly celebrate Independence Day, but it took a while to build up to modern-day festivities.

The first anniversary drew fireworks, a 13-shot cannon salute and spontaneous jubilee in Philadelphia, but it wasn’t until the War of 1812 that observing Independence Day became common. Back then, the day was often used to coincide with large public events, such as the groundbreaking of the Erie Canal in 1817 and the Baltimore & Ohio Railroad in 1828.

Photo credit DVIDS/Airman 1st Class Alexander Cook

A child waves an American Flag pennant as an F-35A Lightning II flies past the crowd.

6. Americans eventually began celebrating the Fourth of July with parades, flag-waving and fireworks – all things that Adams would have likely approved.

According to a celebration letter he wrote to his wife on July 3, 1776, Independence Day “ought to be solemnized with pomp and parade … bonfires and illuminations from one end of this continent to the other from this time forward forever more.”

A Fourth of July parade in Watertown, Wisconsin, in 1941. | Photo credit John Vachon/Courtesy Library of Congress

7. By the 1870s, July 4 was one of America’s most celebrated holidays.

On June 28, 1870, Congress passed a law making it an unpaid federal holiday. It took 64 more years for it to become a paid one.

Happy Independence Day, everyone! How do you plan to celebrate?

-This article originally appeared on dod.mil in 2015. It has been edited for style, brevity and accuracy in 2019.