It really depends on your definition of "natural". But in the 13th century, all of European land had been managed by humans for millenia [1]. To consider rural England from the 13th century more natural, you would rely on a definition unrelated to untouched land, but that distinguishes "natural" human activity, and, I guess, "modern" activity ?

Anthropic reach extended since then (e.g. compounds tiny enough to get in blood, or scale of activity creating global impact), but when it comes to landscape, we have been the shaping factor for a very long time.

[1]: https://www.researchgate.net/publication/236630316_Open_wood...