Hey Swizzle!
I think you need to focus on the famous people categories since GW and A. Lincoln are already represented.
Benjamin Franklin may be the best chance for you.
Shakespeare's home has already been destroyed (and waymarked)
Ponce de León, Bonaparte, Vasco da Gama, and Carl Linnaeus are likely to be found outside of the US if they exist at all.
William F. "Buffalo Bill" Cody is a possible candidate for you, but a little out of your travelling sphere.
Martin Luther King and John F. Kennedy are just too 20th Century.
Good luck on this challenge and thanks for understanding the post in the spirit it was intended. Intent is so hard to convey over the internet.