Every fourth Thursday of November, Americans gather around tables covered with turkey, potatoes, cranberries, stuffing, and more. Over the feast, they share what they’re most thankful for from the previous year. Some also celebrate the day by watching the Macy’s Thanksgiving Day parade or a football game or even by running a 5K race.

But that’s not how Thanksgiving has always been celebrated. The holiday and the traditions behind it have evolved—from a much-mythologized 1621 harvest feast shared by the pilgrims and the Wampanoag, to a post-Civil-War era patriotic and religious gathering, to the modern holiday focused on good food and spending time with family.

In 1841, Boston publisher Alexander Young printed a book containing a letter by pilgrim Edward