Dudes claiming they are "old stock" or "heritage" Americans. They'll even call other white people who's ancestors weren't here before the Civil War "ellis islanders" and invaders.
As someone who's ancestry has partially been here since the 1690s.. it's a crock of shit and silly as fuck.
The most I've found is stuff from 100 years ago but it's spotty at best. Further back gets difficult because of that.