How did racism begin?

🌹C

I’m having some seriously deep thoughts tonight so bear with me. How did racism and enslavement even become a thing?

Why / who / how was it decided that whites were the superior race? Why was it the black race who we decided to oppress? Why not the other way around?

I just don’t understand how this even came to be. I’d love to hear from someone much more educated than I am on the matter