MINNEAPOLIS (WCCO) — On July 3, 1776, the day after the Second Congressional Congress declared the colonies’ independence, John Adams wrote a letter to his wife, Abigail.

In it, he said he believed July 2nd would be the day to celebrate with “pomp and parade, with shows, games, sports, guns, bells, bonfires and illuminations.”

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“He was off by 2 days,” says Hamline University political science professor Joe Peschek.

For 237 years, Americans have been celebrating U.S. independence on the 4th of July, instead of the 2nd.

“The historical record is murky about just what happened,” Peschek said.

Historians do know the Second Continental Congress approved a resolution of independence on July 2, 1776.

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“What came two days later was the wording or the explanation for why the colonists were taking this action and that’s the Declaration of Independence,” Peschek said.

Historians believe the document wasn’t even fully signed until Aug. 2, 1776.

By 1777, there were celebrations of independence on the 4th. In 1870, it was made a national holiday.

“The fourth has become the 4th,” said one woman at the Richfield 4th of July Family Night. “When you say the 4th, you know what it means.”

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Peschek says the minutes of the Second Continental Congress were not taken with the detail of the Constitutional Convention 11 years later and the written recollections of those who were there differ.

Heather Brown