The landmark treaty between the English colonists and Native Americans that established a framework for coexistence was the 1621 Treaty of Plymouth. This agreement was between the Pilgrims of the Plymouth Colony and the Wampanoag tribe, led by Chief Massasoit. The treaty was essential for mutual protection against common enemies and facilitated trade between the two groups. It marked the beginning of a relatively cooperative relationship, characterized by the famous first Thanksgiving celebration in 1621. However, this period of harmony was short-lived, as subsequent conflicts and colonization led to significant tensions and hostilities.