Jamieson, Fausset and Brown on Genesis 10:11

11. Out of that land went forth Asshur--or, as the Margin has it, "He [Nimrod] at the head of his army went forth into Assyria," that is, he pushed his conquests into that country.

and builded Nineveh--opposite the town of Mosul, on the Tigris, and the other towns near it. This raid into Assyria was an invasion of the territories of Shem, and hence the name "Nimrod," signifying "rebel," is supposed to have been conferred on him from his daring revolt against the divine distribution.