No one knows when the first Thanksgiving celebration occurred. For the Pilgrims, a thanksgiving was a religious holiday, in which they would thank God for a specific event, such as winning a battle. For the native Americans, thanksgiving was part of a daily routine for all the gifts of life. Therefore, to refer to the harvest feast of 1621 as the first Thanksgiving is categorically false.
And this feast actually occurred sometime between Sept. 21 and Nov. 11, according to historians, and unlike modern traditions, it was three days long.
It wasn’t until the American Revolution in the 1770s that the Continental Congress suggested a national day of thanksgiving. And in 1817, the state of New York adopted Thanksgiving Day as an annual custom, and many states soon followed.
Finally, in 1863 President Abraham Lincoln appointed a day of Thanksgiving as the last Thursday in November, which many historians believe was in correlation with the anchoring of the Mayflower at Cape Cod in November 1620.