The Kittitas acquired horses by the 1730s, and traded for cattle and western vegetables with the Hudson's Bay Company outpost at Fort Nisqually.

Fur trader Alexander Ross was the first European to enter the Kittitas Valley, encountering a large tribal gathering in 1814.This mammoth camp could not have contained less than 3000 men, exclusive of women and children, and treble that number of horses.

Councils, root gathering, hunting, horse-racing, foot-racing, gambling, singing, dancing, drumming, yelling, and a thousand other things which I cannot mention, were going on around us.

A small group of Catholic missionaries arrived the following year and constructed the one-room Immaculate Conception Mission on Manastash Creek in July 1848.

Father Pandosy headed the mission, but fell into poverty and mental disturbance, and was recalled to the Yakima Valley in September 1849.