Walla-Walla was a very central location for native-white relations. Fort Nez Perce, Fort Steptoe, and the Whitman Mission—including its location near the Columbia River—makes Walla-Walla a nexus point for the whole of Eastern Washington. Consequently, Walla-Walla was one of the most important centers of native-white interaction and exchange along the Mullan Road.
The Nez Perce and the Cayuse are closely associated with the Walla-Walla region and its surroundings. So much so that the name Walla-Walla comes from the Nez Perce and Cayuse word for running water. Lewis and Clark knew the area as Wollah Wollah. The Nez Perce referred to the people that lived by the river (the Cayuse) as “Little River People,” or the “Walawalapu.”
Though the Nez Perce and the Cayuse were closely related, there are some significant differences between the two groups: the most important of which is the areas that each Native group chose to live in. It was the high country rather than the river areas that the Nez Perce preferred to live in. For this reason, they inhabited the mountainous areas—along high rivers and valleys—that surrounded the various communities of the northwest.
The Cayuse, on the other hand, preferred the low river locality, along with the lifestyle the location engendered, rather than the mountain regions. Consequently, the river area was where the main Cayuse community, called Waiilatpu, made their homes.
Shoalwater Bay Heritage 