struck me as unfamiliar.
Nope, it’s been quite familiar to even someone several hundred years ago.
Europeans civilization are 1000s of years old, America is a baby compared to them, the history and memory are very different.
That really depends on what's your definition of "Europeans" and "civilized". The Catholic church exists for around 2 thousand years,is still alive and well, has its capital in Italy, and has defined western society for centuries.
Yes, my house is older than the United States. We found pieces of journals talking about the General Bonaparte. It's pretty common to find stuff from several centuries ago in old buildings.
The Romans built roads, aqueducts, houses with central heating and massive great walls across the landscape.
They might have been violent but it’s hard to claim they weren’t a civilisation.