I like how the most popular and vulgar ones are Germanic. It kinda explains a lot about how we identify 'swear' words.

Also, the severity/vulgarity of these words seems to vary across culture as well.

Here, we use 'shit' way too liberally than in the West. It's surprising because until we go to university and engage with professors from the Western world, we didn't know that 'shit' is right up there with 'fuck'. To us, it's probably right above 'damn', and way below 'bitch'.