Deriving nouns and adjectives from place names

List of adjectival and demonymic forms of place names

The following is a partial list of adjectival forms of place names in English and their demonymic equivalents, which denote the people or the inhabitants of these places.

The list can be found here on Wikipedia

Note: Many of these adjectivals and demonyms are not used in English as frequently as their counterparts in other languages. A common practice is to use a city's name as if it were an adjective, as in "Vienna Philharmonic Orchestra", "Melbourne suburbs", etc.

New York can also be used as an adjective without changing it's form.

A map of adjectival forms of place names

can be found here

It's a bit hard to grasp the question you are asking, particularly because your entry contains misconceptions. For example, the words in examples 1-3 are adjectives, but they are not based on place names but rather on the names of nations or ethnic groups. So, we have Chinese, Danish, Iroquois, Jewish, and Turkish but not *Akronian (from Akron, Ohio).

Similarly, although some of the words employed to refer to people on the basis of their national, ethnic, or geographic origins, as in examples 4-6, look the same as the previous set--notably American and Canadian, many are not--and the plural inflections that appear on American and Canadian in the plural show that they are indeed not adjectives but nouns. Other examples than New Yorker include Dane, Hoosier, Illini, Iroquois, Jew, and Turk. Instructively, we do not put *Chinaman in this set because of its history of pejorative usage, but instead would say, I think, "They are from China."

Similarly, if the other terms were to become dysphemic, I believe we would say "They are from Denmark", "from Indiana", "from Illinois", and "from Turkey", but "members of the Jewish nation" or "of the Iroquois nation." Thus, word-formation processes differ across types of words in ways that go well beyond the adjective/adjectival-noun dichotomy your question employs.

As I said, I am not sure your question is well posed, though the issues it raises are complex and quite interesting. I wish that I had more to say.