@koanhead
That sounds like a fun book- have to see if I can get a copy!
One small thing for the OP- just be aware that the “blackberries” referenced are the native species like Rubus ursinus, not the terribly invasive and non-native Himalayan and evergreen blackberries which came much later. (I have to admit a personal loathing for these non-natives- my peaceful soul screams “Die, die, die!” and I chuckle with glee when I see the spots of rust enervating their leaves…)
“Other tribes lived in the high desert east of the Cascade Mountains- is that still Western Washington?”
Nope- east of the Cascades is Eastern WA :>)