A 17th Century African Burial Ground

In 1991, a lower Manhattan excavation for a new federal building unearthed a 17th-century burial ground where enslaved Africans were interred between the 1690s and 1790s. The site is considered New York City’s earliest African American cemetery and was named a National Historic Landmark in 1993, followed by a National Monument in 2006.
I'm wondering, if s/o writes:
"Faaaake - how can it be?
The US exist since 1776-07-04 ! Nothing can be before!
Don't be a woke leftist, do your own research, touch some grass and never trust science or the universities!"
Bomb! What the fuck?