Ashur vs Assur

Ashur and Assur both are nouns.

Word	Noun	Adjective	Verb	Adverb
Ashur	Yes	No	No	No
Assur	Yes	No	No	No

As nouns, Ashur and Assur are synonyms defined as:

Ashur and Assur: an ancient Assyrian city on the Tigris and traditional capital of Assyria; just to the south of the modern city of Mosul in Iraq

Other synonyms of Ashur include Asur.

Ashur (noun)	Assur (noun)
an ancient Assyrian city on the Tigris and traditional capital of Assyria; just to the south of the modern city of Mosul in Iraq	an ancient Assyrian city on the Tigris and traditional capital of Assyria; just to the south of the modern city of Mosul in Iraq
chief god of the Assyrians; god of military prowess and empire; identified with Babylonian Anshar