I'm so used to Poke being a nickname that OSU fans use, that I didn't realize DCPoke was a Wyoming fan.
Actually Wyoming is the original Pokes or Cowboys. UW took the mascot name in 1891 as the players on the first team were cowboys. OSU were the Tigers or the Aggies up to 1923 and then switched to the Cowboys.
From the UW media guide:
The nickname “Cowboys” was applied to Wyoming athletic
teams as early as 1891 - two years before the first official
football game. The story is that the Wyoming pick-up
football team appealed to a 220 pound cowpuncher, Fred
Bush, for help in a game against the Cheyenne Soldiers.
Bush signed up for a course or two and came out for
the team. When he trotted onto the field decked out in a
checkered shirt and Cowboy hat, someone yelled, “Hey, look
at the Cowboy!” Since many of the members of the team
were also ex-cowboys, the name stuck. When women’s
sports were added at UW, the nickname of Cowgirls was
applied to those squads.