here appearances of that city in Poul Anderson's works so I need not repeat that now but here is another thought. I often mention New York on this blog if only as the place of publication of Anderson's works.
When we hear or read the phrase "New York," we think of that place across the Atlantic with all the skyscrapers and the Statue of Liberty. We do not think, "a new city of York," although that is what the phrase originally meant.
York and New York are simply different places with distinct, indeed opposite, identities. There is even a chain of "New York Italian Restaurants" in Britain! And there might even be one of those in old York... Can anyone out there, on this side of the Atlantic, confirm that?
Addendum, 30 Nov: I googled. There are two New York Italian Restaurants in old York.