Gdansk vs Danzig

Gdansk and Danzig both are nouns.

Word	Noun	Adjective	Verb	Adverb
Gdansk	Yes	No	No	No
Danzig	Yes	No	No	No

As nouns, Gdansk and Danzig are synonyms defined as:

Gdansk and Danzig: a port city of northern Poland near the mouth of the Vistula River on a gulf of the Baltic Sea; a member of the Hanseatic League in the 14th century

Gdansk (noun)	Danzig (noun)
a port city of northern Poland near the mouth of the Vistula River on a gulf of the Baltic Sea; a member of the Hanseatic League in the 14th century	a port city of northern Poland near the mouth of the Vistula River on a gulf of the Baltic Sea; a member of the Hanseatic League in the 14th century