But you totally contradicted yourself in the latter half of your argument.
I was only trying to say that, as the identification of a region's name with its main city's name happens all too often in Mystara, there'd be no need to have another example of it, mostly when we have two official names to work with (like New Grunland and Jelden).
Anyway, it was only an idea - I mean, if I'd ever play in the Shadowlands (yes, I never did nor sent my PCs there!
), I'd favor the name 'Jelden' for the city.
Besides, there are many more real world examples that you didn't mention.
Note that ALL Italian provinces have their capital's name (i.e. city of Milan in the Province of Milan, city of Naples in the Province of Naples, and so on). But please note also that in cases such as these - and the ones you mentioned above - we aren't talking about historical names, but about administrative labels chosen LATER by national states.
Thus, names chosen in this way could IMO apply mostly in one of two instances: (1) a city which later expands to become a larger state (like the Republic of Venice, of the Empire of Rome), or (2) a region which is later given its main city's name becouse it's its most prominent feature (like the State of New York, or the moorish Kingdom of Granada).
All in all, I don't know how many times this could apply on Mystara.
For example, names such as Glantri and Darokin have been added later to the respective countries to represent their founder's name (as if the 13 North American colonies would have chosen in 1776 the name "United States of Washington"), while other such as Minrothad and Ylaruam take their main city's name as the country's name ("United States of Philadelphia", or "of New York", or something like that). Anyway note that these are all politically-chosen names, not historically-stratified ones: neither Darokin nor Glantri or Minrothad was ever called by that name before the birth of a particular political regime.
Now, to come back to the "New Grunland-Jelden" issue, as Grunland was a region's name I think it difficult that the Shadow Elves would have chosen it as the name of a city. I mean, New Spain wasn't the name of a city, but of old Spanish Mexico (IIRC), and the same it's said about New Holland (nowadays Australia), or New England, or New Zeeland (Zeeland is one of the Netherlands' historical provinces).
So, I don't mind keep calling the city New Grunland, and I'd not commit suicide if you cast away the 'Jelden' label, but I only reasoned that IMHO it'd make more sense if New Grunland applied to the region rather than the city.
"The prince should study historical accounts of the actions of great men, to see how they conducted themselves in war; he should study the
causes of their victories and defeats, so as to avoid the defeats and imitate the victories" N. Machiavelli, The Prince, XIV, 5