The Tonawanda Seneca Nation (previously known as the Tonawanda Band of Seneca Indians) (Seneca: Ta:nöwö:deʼ Onödowáʼga꞉ Yoindzadeʼ) is a federally recognized tribe in the State of New York. They have maintained the traditional form of government led by sachems (hereditary Seneca chiefs) selected by . The Seneca are one of the original Five Nations (later six) of the Haudenosaunee or Iroquois Confederacy. Their people speak the Seneca language, an Iroquoian language.