History of July 4th

Presumably everyone who is affected the July 4th holiday in the United States knows of the historical events it commemorates.  But I thought it interesting that Independence Day wasn't made a federal holiday until 1870 (after the Civil War) and even then it was an unpaid holiday.  (Is that really a holiday at all, then?) It wasn't declared a paid federal holiday until 1938.

I also thought it was interesting trivia that both John Adams and Thomas Jefferson, each a Founding Father and later a U.S. President, died on July 4, 1826.