This is all head canon and I don’t feel like looking it up, but they didn’t invent racism, they just invented whiteness.

That’s why Irish people were discriminated (and genocided) against until someone in the 20th century. Now Irish are white. People made a huge deal about JFK being a Catholic president because he wasn’t “one of them.” Now Catholics are indistinguishable from other white crowds. They speak with one voice (in their minds, not a real generalization).

Jews were on their way to whiteness and then Trump happened in 2016 and the old conspiracy theories became relevant again, and now they’re back to being separate.