Wow shocking archival discovery...
https://twitter.com/TheViewFromLL2/status/1273983838256074753

Sorry for sarcasm it's a good thread and important story but the implication that this wasn't known til now, unearthed in some dusty file, is insanely misleading.
Daniel Crofts, one of the preeminent Civil War era historians we have, published a book on "the other thirteenth amendment" only four years ago.
The breathless heavyhanded narration: "Then I kept resding." Commenter: "holy. shit." Please! We have much work to do to give the public a less caricatured version of US history, esp re the Civil War; I don't know what is served by the suggestion that these are new discoveries.