The first feast wasn't repeated, so it wasn't the beginning of a tradition. In fact, the colonists didn't even call the day Thanksgiving. To them, a thanksgiving was a religious holiday in which they would go to church and thank God for a specific event, such as the winning of a battle. On such a religious day, the types of recreational activities that the pilgrims and Wampanoag Indians participated in during the 1621 harvest feast--dancing, singing secular songs, playing games--wouldn't have been allowed. The feast was a secular celebration, so it never would have been considered a thanksgiving in the pilgrims minds.

The original feast in 1621 occurred sometime between September 21 and November 11. Unlike our modern holiday, it was three days long. The event was based on English harvest festivals, which traditionally occurred around the 29th of September. President Franklin D. Roosevelt set the date for Thanksgiving to the fourth Thursday of November in 1939 (approved by Congress in 1941). Abraham Lincoln had previously designated it as the last Thursday in November, which may have correlated it with the November 21, 1621, anchoring of the Mayflower at Cape Cod.