Note that the caribou were in Boundary County. Caribou County does not have Caribou and never has in recorded history. So why would you name a county after caribou that never get closer than, say 480 miles away?
Residents are quick to tell you that Caribou County is not named after any sort of reindeer. And they are mostly correct. The county is named after “Carriboo” Jack Fairchild, a miner who was among those who first discovered gold on what is now called Caribou Mountain.
But one must wonder where Carriboo Jack got his name. As it turns out, the inveterate storyteller got his nickname because when questioned about the veracity of one of his stories he would often reply, “It is so, I will let you know I am from Cariboo.”
The Cariboo he was from was a mining district in British Columbia, where Fairchild had also worked a claim. The area retains the spelling, with a single “r” today. Carriboo had the extra “r” in his name because, I don’t know, he deserved it? And why don’t the Canadians spell it caribou?
The county in Idaho was called Carriboo until 1921, when someone decided to “correct” it. Caribou Mountian, Caribou City, and the Caribou National Forest all owe their name to Cariboo Jack, the story teller.
One story he often told was about his origins. “I was born in a blizzard snowdrift in the worst storm ever to hit Canada. I was bathed in a gold pan, suckled by a caribou, wrapped in a buffalo rug, and could whip any grizzly going before I was thirteen. That’s when I left home.” A guy like that can spell his name any way he wants.
Much of this story comes from a piece Ellen Carney wrote for the Caribou County website.