The Native American tribe that celebrated the first Thanksgiving with the Pilgrims was the Wampanoag tribe. They helped the Pilgrims survive the harsh first winter by sharing their knowledge of farming and local resources, and the 1621 harvest feast, considered the first Thanksgiving, was attended by Wampanoag men led by their leader Massasoit alongside the Pilgrims. This event lasted for three days and included sharing of food such as deer and corn, and various activities like games and dancing.