People genuinely do not understand history.

I think a good comedic example of this is in Futurama, where some characters from the year 3000 get tossed back to Roswell in 1947. They try to blend with "period correct clothes" and lingo, but since they're 1000 years out of place, they're combining things that hadn't been invented yet with stuff from 1947s past.

A lot of people seem to think cleopatra was hanging out with the dudes who built the pyramids and think it's weird Sparta and Rome never went to war. I mean, sure technically they both existed in an overlapping period of about 50 years, but technically the USA has had diplomatic contact with the Holy Roman Empire for a few years.

Imagine if a shuttle landed on the planet and someone from 2402 popped out with their neon implants, xarthan death spikes proudly displayed, and an onion on their belt. Everyone knows they don't show up until at least 2215.