It's really quite astounding, especially considering hostility towards non-white people is a very recent 'innovation' of European culture, and one that the world should all be glad to be ridding ourselves of.
You'd be surprised. Medieval and early Renaissance Europe were far from culturally sensitive*, but they regarded people in Asia and Africa as fundamentally similar to themselves. Racism evolved out of the discovery of the New World - at first, as a means of justifying the murder and enslavement of American peoples, and then, after the Pope said that colonizers had to pretend to care about Christianized native lives, as an excuse to seek exploitable labor elsewhere (Africa). Even in the 17th century the divides were far from firm - only going into the 18th did social divisions harden, and not until the end of the 18th century did 'scientific' racism truly emerge.
*my personal favorite is in a 12th or 13th century chivalric romance, a character is mixed-race - the European author apparently had no idea what someone who's mixed race would look like, and so described them as literally half-white and half-black, split down the middle
A translation from German, and an older translation at that, so keep that in mind, but it's actually a pretty fun, if very, uh, Medieval European, story.
Most US Americans are protestants, because we have religious cultural roots with later British and Dutch settlers. But the first colonizers of North America and South America were the Spanish and Portuguese, who are very Catholic, and they dominated colonization efforts for some 200 years.
Racism has been present for a lot of human history. The modern western version of Christian white supremacy can be traced back to the Greeks, then on to the Arabs who, inspired by the Greeks, used their conception of race to justify their already present slave trade. For the Arabs it's wasn't so much "we're superior so we have a right to enslave these people" as it was "we were able to enslave these people because we are superior". European Christians, armed with "the curse of ham" took those Greek ideals and pushed racial heirarchy and supremacy to the cultural forefront around the 15th century and it's shaped their societies, colonies or otherwise ever since. It's obviously evolved and changed over time but that's the gist of it. Racism isn't new, but European christian empires made it into the monster it is today