I was born and raised in Nampa, just 20 miles west of Boise. Black and brown people had nothing to do with building that area. There may be a lot of Mexicans working agriculture today, but when it was being built up, it was white people who did that building. My family has been in Idaho over 100 years.
I’m guessing lots of yellow people helped build the railroad that brought in most of the material into Boise. I didn’t see their color mentioned.
BTW - the first time I heard the term “brown people” was only a few months ago. Maybe I had heard it before but didn’t notice. Now it is everywhere.
My dad grew up in Glenns Ferry. The only blacks he ever saw before leaving Idaho were Pullman porters. So blacks and browns had little if anything to do with building Idaho.
NJ wasn’t originally built by blacks and browns either; I don’t think I’ve even seen any claim to do so.