"My country's history is one of manufactured suffering. I was a boy when the Tudors burned any food the rebels under O'Neal might think to eat. We starved, everyone starved. Mouths on the dead stained green from chewing nettles. You get resourceful in a famine. My parents died early. Left me and my sister catching rats. The rats ran out quick. Fed my sister on my blood. It kept her alive an extra...two weeks. I didn't sleep for three days to protect her body from the starving till the ground thawed. I cut out her kidneys and buried her. Fat cap on them like a pea. I haven't eaten a single meal since, my mind didn't go to that bite. It was the last thing I ever did because I had to. I control my life now. Every bite."

-Abijah Fowler in Blue Eye Samurai

Also, later in the show:

That first line has stuck with me though since I first heard it. "My country's history is one of manufactured suffering." That could be about any country in the world, and it would still ring true in some form or another. The worst monsters to ever walk this planet have all been human.

The difference with the "over a longer time" thing is that no one would expect people in like 500 CE to have similar values to us, meanwhile countries like 19th century-onwards USA explicitly pride themselves on equality, including between races (after 1866, anyway).

Well, I am sure there must be some really remote desolate land somewhere that no one had claimed. And of course the native Americans didn't believe in owning land, so it is a bit fuzzy "technically". But we all know what happened...

I'll let you know if we ever get there.