American Thanksgiving is celebrated annually on the fourth Thursday of November to commemorate the harvest feast shared between the English pilgrims and Wampanoag Indians in 1621. The pilgrims arrived in North America in December 1620 after a difficult crossing of the Atlantic Ocean aboard the Mayflower and received assistance from the Wampanoag in learning to cultivate the land. In the autumn of 1621, the surviving pilgrims and Wampanoag Indians gathered for a three-day feast of turkey, corn, and other foods to celebrate their first successful harvest in Plymouth, Massachusetts, establishing an annual tradition now celebrated as a national holiday in the United States.