Fascinating how expressive just solid-colour squares can be. In his "The Assassination of Julius Caesar" video near the end, seeing the red square wiggle and then spin felt very emotional.

Is there a name for this type of animation style?

One of the best history channels on YouTube IMO. Have learned an incredible amount about miscellaneous history, Roman culture and politics, and the gritty details of wars from the past. Check it out and support them on Patreon!
Is this related to Peter Turchin's book of the same name? I can't tell from reading their site ( if that's the case.
This channel is very nice. The Alexander and the Caesar in Gaul videos are my favourites.