Long before Juan de Fuca passed through the straits in 1592, there were dozens of Indian tribes who pursued their livelihood by fishing, gathering roots and berries, harvesting shellfish and hunting in the area which was to become Washington State. The Yakama Tribes occupied nearly 17,000 square miles of this area. Their land extended from the summits of the Cascades on the west to the Palouse area of the Columbia Basin on the east. The northern border extended into British Columbia, and the southern border into Northern Oregon. Within this area there were many small tribes and bands of Indians possessing a similar way of life.
In the summer of 1855, a Treaty Council was convened at Walla Walla, and the Yakama Tribes were pressured to cede 16,900 square miles for a reservation of 1,875 square miles and reserved rights and guarantees.
In 1988, Congress passed the Indian Gaming Regulatory Act establishing a legal basis for the right to conduct gaming on reservation land.