Backround and PoD: It is 1805, and Lewis and Clark are attending a meeting of Pacific Northwest chiefs at the Dalles. When Lewis and Clark (LaC) propose that the Indians' lands be absorbed into the US, (heres the PoD) several chiefs protest, most vocally the Tlinglit, Blackfoot, Cayuse, Paiute, and Chittanoosh (Nez Perze). LaC leave the meeting dissatisfied and begin the long journey back home. However, along the way they are attacked and massacred by Blackfoot warriors. Meanwhile, the Chittanoosh propose a confederacy of the various western tribes to protect against European encursions.
The confederacy is formalized in 1809, with the capital at Dalles. It has almost 300,000 people, and stretches N-S from the Fraser to Sacremento, and E-W from Pacific to western Montana.