I know the south shifted Republican after the Civil Rights Act passed in 1964 but West Virginia is more of a mystery to me. It started out as a state that rebelled against the south and slavery, it's fairly far north and yet seems to have fallen to a similar pattern.
So my question is what made it a solid Democrat state since the 1930s to a solid Republican state by the 1990s? Was it a cultural/economic shift or something else?
Short answer -- A combination of the death of the coal industry (and therefore labor unions) and disinvestment by the the Democratic Party. But this is a very complex question with both historical and political causes. I have tried to include both below with more attention given to historical causes, but there's a lot of current public sentiment guesswork that we, as historians, just cannot answer.
Becoming a solid red state was also more recent of a shift than you think. West Virginia had full Democratic state control until 2010 even though the state has voted Republican in the Presidential election since 2000. That was the year the WV's U.S. House vote went from 2D/1R to 2R/1D. Things continued to drift Republican until 2016 when virtually every election went Republican except for Senator Joe Manchin and Governor Jim Justice (who switched his party allegiance the next year). So I would argue WV was Solid Blue to 2000, then "purple" to 2012, then finally Solid Red by 2016 or so.
The origins of West Virginia Democratic success begins with the Great Depression and the 1932 election, but these were Democrats in name only at first. As is well-documented, Republicans led by President Hoover utterly failed to manage the economic crisis, so you see this shift to Democrats everywhere, including West Virginia. Ironically though, West Virginia's two Democratic governors of the 1930s -- Herman Kump and Homer A. Holt -- were anti-union conservatives. They both actively resisted New Deal programs, instead favoring austerity with a little bit of corruption on the side. The same was true, to a lesser extent, of WV's senior Senator Rush Dew Holt, but their junior Senator who would be elected Governor in 1940 -- Matthew Neely -- was a pro-union New Deal Democrat through and through. From that point forward, Democrats generally held onto state power with a few minor losses here and there roughly tracking national politics (for example, Republicans win Neely's Senate seat when he runs for Governor, and Democrats only win it back when Neely runs for it again in 1948).
The next thing to understand is the War on Poverty and Robert Byrd, easily the state's most important post-WWII politician. The War On Poverty was a late-1960s Federal initiative to combat poverty in both Appalachia and inner cities. You probably can't drive more than 20 miles before you see something named for Byrd. But the reality is that Byrd did secure plenty of Federal money for West Virginia, but he never built out a strategy that would last beyond himself. It was all personal patronage. A bill needs Byrd's vote? Well, toss something in there to, for example, funding a biotechnology center at Marshall University or a new visitor center at Seneca Rocks. This isn't to totally fault Robert Byrd -- he was just Doing What Politicians Do -- but he never forwarded a poltiical strategy that could both support a transition for workers away from the WV coal industry and allow for pro-environment legislation. As for the War on Poverty, most historians would agree this initiative failed, but at the very least it renewed attention to poverty in Appalachia. Even if life wasn't made noticeably better, at the very least West Virginians understood the Federal government was trying to do something. See Huey Perry's book below for how a well-meaning program utterly failed when it was put into action.
That brings us to the 21st century. The coal industry is dead. West Virginians know this, but if you live in somewhere like Mingo County, what else is there to do? Literally nothing else in the area can promise you a decent income. Plenty of people on this very website would say "well why don't they just move," which is just an impossible, impractical solution for people trapped by capitalist inequalities. Such people are further exploited by culture war campaigns (see "Friends of Coal") and the opioid epidemic which, as we know 100% now, was engineered by Big Pharma companies like Purdue Pharma.
Imagine you area young adult in West Virginia around the year 2012. Robert Byrd is dead. Democrats have not passed any legislation recently that has made your life noticeably better compared to your parents (War On Poverty + Appalachian Regional Commission) and grandparents (New Deal). There are few Federal programs to help you out. The Appalachian Regional Commission has hardly any money anymore. You choices are to (a) try to get one of very few coal jobs that pay well, (b) take a poor-paying job at a gas station or dollar store, or (c) go to college. Sadly, (c) just isn't an option for many people. It then makes sense why someone would buck the political party that controlled the state for ~70 years. Why continue to vote Democrat? They largely abandoned West Virginia a long time ago.
Also, a final point -- voter turnout is horrible in West Virginia. Trump won West Virginia in 2016, but more West Virginians chose not to vote at all than voted for Trump. Keep that in mind when labeling a state "Red' or "Blue". In West Virginia, many people started voting for Republicans in the hopes they would do something to help them out, but even more just stopped voting altogether largely because they believe help isn't coming at all.
If there's anything here anyone would like me to expand upon, please just let me know. Really tough question to condense into a single post.
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