Haida are North American Indigenous people who have traditionally occupied the coastal bays and inlets of Haida Gwaii (meaning “island of the people”) in British Columbia.
 
Tsimshians are North American Indians of the Northwest Coast who traditionally lived on the mainland and islands around the Skeena and Nass rivers in British Columbia, Canada and Alaska.
 
Chief Seattle mentions these two tribes as the Red Indians’ “ancient enemies far to the northward” who understandably used to “frighten (their) women, children, and old men“.

As seattle says the two tribes are an enemy of red indians. He uses their names many times in the speech which shows that he is concernd for his people and ask them to take care