Use of the definite article with names of regions

Question

Should I use a definite article with names of regions? E.g. (the) Zemplin region, (the) Košice region (administrative unit).
Zemplin and Košice are Slovak proper nouns.

Answer 1

Proper nouns have a "built-in" determiner and don't need articles.

I talked to John.

I talked to the cat.

However, you are using both names as adjectives to describe the noun region, so you still need the determiner.

If you were using the words as nouns then no determiner needed since they'd be proper in English too.

I went to the Zemplin region.

I went to Zemplin.