Controlled Alberta for decades and BC as well though in BC it transformed into more of a big tent "everyone but the NDP" conservative party. Still run by lunatics though.

In Saskatchewan prairie populism took a left wing form instead.

In Alberta the taint of these people never went away. Lougheed's progressive conservatives pulled Alberta governance a bit more mainstream for a couple decades, but Smith's UCP has dragged it right back. Magazines like Alberta Report and hangers-on kept far right prairie right wing populism alive for decades, Preston Manning (Social Credit premier Earnest Manning's son) "mainstream"ized it in the Reform Party ... which essentially took over the federal conservative party... there's a well-spring of this stuff in rural Alberta.. and its full of all sorts of paranoid persecution complex politics, undertones of anti-Semitism (sometimes outright explicit as in the whole James Keegstra afair), with everything to the left of them considered "communism" and these days with bags of money being dumped on them from the US they have no managed to get themselves enough signatures to force a referendum on "independence" (aka annexation by the US).

As a person from Alberta originally and with all my family still there, I find it all a bit terrifying. Very much not a relic of the past, and with COVID and now Trump the lunatic fringe has outsized influence there like it never did before.

I suspect if you probe the right people from the UCP in the right church basements where they're off-mic you'd still find them defending things like eugenics etc.