Why is it that the country of Nederland, singular in Dutch, is called 'The Netherlands,' plural in English?

https://en.wikipedia.org/wiki/Netherlands_(terminology)

I think this is the link you were looking for.

https://en.wikipedia.org/wiki/Netherlands_%28terminology%29

Let's not post a link without an answer, please.

"Netherlands" literally means "low countries" or "lowlands". The Netherlands is among a small number of countries which have a singular name for their country, while the English language uses a plural form. This plural convention is actually an archaic term, referring to the period 1581 to 1795 when the Dutch republic was a loose confederation of seven provinces. The name in the Dutch language is Nederland (low country) while the Dutch republic is referred to as Republiek der Zeven Verenigde Nederlanden (republic of seven united low countries) or Nederlanden (low countries) for short.

https://en.wikipedia.org/wiki/Netherlands_%28terminology%29#The_Netherlands