On this day in 1970, a group of Native Americans attending a Thanksgiving feast in Plymouth walked out in protest. The Indians and their supporters gathered on a hill overlooking Plymouth Rock near a statue of Massasoit, the Wampanoag leader who had greeted the Mayflower passengers 350 years earlier. The protesters spoke about their long struggle to preserve their land and culture. The fourth Thursday in November was not a day for thanksgiving and feasting, they declared, but for grieving and fasting. As most Americans continued to observe the holiday in what had become the customary way — with football, parades, and family gatherings — the native people of Massachusetts began a new tradition: a "National Day of Mourning," held in lieu of Thanksgiving celebrations.