I learned about them after using "skinhead" in a derogatory way to a music buff. That was the same conversation where I learned that ska is actually older than reggae, which is still wild to me.

Non-racist skinheads pre-date the racist ones.

Ska is a Jamacain music style that white working class British youth got into due to working and living alongside Jamaican immigrants, leading to mixing with punk to create 2 Tone.

The racists started to co-opt and taint the movement later on.

Similar is just actual punk culture in general

I've looked into them too a while ago and the skinhead subculture is pretty interesting. I'm going off of memory but I'm pretty sure the subculture started in London in the 1960s. There were three big subcultures at the time in London, the posh upper class were "mods", the lower class "rude boys" got their influences and style from Jamaican immigrants, and finally the "skinheads" were the middle class had their shaved heads and Doc Martens. The second wave of skinheads in the 70s and 80s in the UK and US were basically anti-punks. They were the punks who were mad about the commercialization of their culture and they shaved their mohawks, traded their battle jackets for flannels, and moved from punk music towards ska. And finally the third wave in the 80s and 90s were the racists who were getting tired of getting their teeth kicked in at punk shows. And since hating people for no reason doesn't have a style or culture of its own, those shitbags (I would argue very successfully) stole the working class style of the skinheads