There are no actual hangings but the museum in one of the episodes show black people with rope on their necks and a diorama of hanged concentration camp victims
In the US episode, a vampires p***k the skin of people they feed off of. Several animals’ throats are slashed, and in the Africa episode, voodoo practitioners slash themselves repeatedly with knives.
Episode 2: Japan. In the Part where David visits Aokigahara he meets a woman who once wanted to kill herself there but didn't. She gets attacked by spirits of the forest.
Season 1 Episode 5: Dave visits the Littledean Jail Museum. Museum owner drops the N-word several times and has an incredibly weird and distasteful way to 'display' history.