If you think Americans have been celebrating Thanksgiving annually since 1621, guess again. Nobody at the time thought of it as the start of a new tradition, and there had been similar gatherings elsewhere earlier. Historians know there was another feast in the colony in 1623 but it was held earlier in the year. Different colonies celebrated their own days of thanksgiving during the year.

In 1789, George Washington declared Thursday, Nov. 26, a Thanksgiving holiday, but only for that year, and it was not connected to the Pilgrim feast but rather intended as a “public thanksgiving and prayer” devoted to “the service of that great and glorious Being who is the beneficent Author of all the good that was, that is, or that will be.”

Enter a 19th century author, poet and magazine editor named Sarah Josepha Hale. She was editor of the influential Godey’s Lady’s Book for 40 years, from 1837 to 1877. Hale, who was highly patriotic, read about the 1621 feast of the Pilgrims and became captivated with the idea of turning it into a national holiday. She published in the Godey’s Lady’s Book recipes for turkey and stuffing and pumpkin pie and started traditions that had nothing to do with the colonists. She began a lobbying campaign to persuade President Abraham Lincoln to make Thanksgiving an official annual holiday, using her magazine to build public support by writing an editorial every year starting in 1846. She also sent letters to all governors in the United States and territories. In 1863, Lincoln did set Thanksgiving as an official holiday to be celebrated on the fourth Thursday of November every year.

In 1939, President Franklin D. Roosevelt agreed to move the annual Thanksgiving holiday to the third Thursday of November. Why? To help the economy by making the Christmas shopping season a little bit longer. There was so much opposition to the move, that two years later he changed it to the fourth Thursday in November.