Historian and archeologist Kelley Fanto Deetz arrived to work at Virginia’s Executive Mansion last month to find her office had been emptied. Items in a historic kitchen in the building’s annex, which had been reimagined to tell the stories of enslaved workers to visitors, had been shoved aside, she said. A planned educational room for schoolchildren was empty except for a TV, leading Deetz to conclude it had been reconverted into a family room for Republican Gov. Glenn Youngkin. Deetz is unsure whether she still has a job as the mansion’s director of historic interpretation and education. Deetz’s work updating...