On July 2nd, the Continental Congress voted in favor of independence, and two days later its delegates adopted the Declaration of Independence, a historic document drafted by Thomas Jefferson.
From 1776 until the present day, July 4th has been celebrated as the birth of American independence, with typical festivities ranging from fireworks, parades and concerts to more casual family gatherings and barbecues.
Adams and Thomas Jefferson both died on July 4, 1826--the 50th anniversary of the adoption of the Declaration of Independence.
John Adams believed that July 2nd was the correct date on which to celebrate the birth of American independence, because on July 2nd, the Continental Congress voted in favor of Lee’s resolution for independence in a near-unanimous vote (the New York delegation abstained, but later voted affirmatively).
On that day, John Adams wrote to his wife Abigail that July 2 “will be celebrated, by succeeding Generations, as the great anniversary Festival” and that the celebration should include “Pomp and Parade…Games, Sports, Guns, Bells, Bonfires and Illuminations from one End of this Continent to the other.”
On July 4th, the Congress formally adopted the Declaration of Independence, which had been written largely by Jefferson not Adams. Though the vote for actual independence took place on July 2nd, from then on the 4th became the day that was celebrated as the birth of American independence.