>>44251295the way I was explained:
Duits/Diets/Deutsch all come from a germanic word meaning "of the people".
In the middle ages they referred to dialects spoken by regular people in the Low Countries (and Lower Germany) as opposed to the clergy with their Latin and the nobles with their French and other fancy languages.
There's still a Dutch word "duidelijk" which means "clear/understandable". Languages like Middle Dutch were written but still subject to dialect influences.
Terms like Netherlands/Nederlanden/Low Countries only became popular after the middle ages when the later Netherlands became part of the Burgundian political sphere. Germany/Germania/others was probably used for what the Romans considered Germania or where the German/Dutch dialects were spoken. There's also the fact that aside from the County of Flanders all Germanic-speaking parts of the Low Countries were in the HRE.
While the English did have a lot of trade contacts with the Low Countries (after all the best clothmakers in Europe will buy the best wool in Europe) they still considered them as one with the other Germans (which was probably accurate until the Burgundians started inheriting shit). I guess the name stuck for the Dutch people and "German" became associated with the rest.
Things aren't made less confusing by the fact that the West-germanic language continuum is a little messy (partially due to standard Dutch and standard German being artificially constructed from natural dialects). pic related