"Nineveh (Assyrian city of "Ninua") was an important city in ancient Assyria, lying within the area of the modern city of Mosul in Iraq. This "exceeding great city" as it is called in the Book of Jonah, lay on the eastern bank of the Tigris, along which it stretched for some 50 kilometres (30 miles), having an average breadth of 20 km (10 mi) or more from the river back toward the eastern hills. This whole extensive space is now one immense area of ruins.
Situated at the confluence of the Tigris and Khosr, Nineveh was an important junction for commercial routes crossing the Tigris. Occupying a central position on the great highway between the Mediterranean and the Indian Ocean, thus uniting the East and the West, wealth flowed into it from many sources, so that it became one of the greatest of all ancient cities."
But I think there is a Catholic site that may say differently.
Here we go from New Advent
http://www.newadvent.org/cathen/02007c.htm"Nineveh (in the Douay Version, Ninive), represented by the villages and ruins of the modern Kujunjik and Nebi-Yunus, on the eastern bank of the Tigris, opposite Mosul. Nineveh was undoubtedly one of the most ancient cities of Assyria, and in the time of Sennacherib (7th cent. B.C.) it became the capital of the empire, and the centre of the worship of Ishtar, the Assyro-Babylonian Venus, who was called Ishtar of Nineveh, to distinguish her from Ishtar of Arbela. In the Old Testament the city of Nineveh is well known in connection with the prophets, and especially as the theatre of Jonah's mission."
Those Assyrians have been around for quite some time. :eyes: