https://newsone.com/3853253/african-americans-founded-memorial-day/
https://time.com/5836444/black-memorial-day/
https://www.history.com/news/memorial-day-civil-war-slavery-charleston
“It‘s the fact that this occurred in Charleston at a cemetery site for the Union dead in a city where the Civil war had begun,” says Blight, “and that it was organized and done by African American former slaves is what gives it such poignancy.”