The guy in the thumbnail is from the channel Esoterica. He seems to be one of the guests on this video and if you ever want a extremely well researched look into the history of the occult he's amazing. Also fun fact he almost got prosecuted as a teen as part of the Satanic Panic here in the US.
Came here to educate the masses about Dr Justin Sledge as well. He has one of the best channels on Youtube, period. Scholarly content mixed with some humor and ridiculously interesting topics.