'Civilization V' strategy: Ashurbanipal, the Assyrian tech-thief

I have not had a chance to play all the new civilizations in the Brave New World expansion. Each new civilization is pretty interesting though, as they all have very unique bonuses and utilize novel game mechanics. I am planning on writing a brief strategy post about each of the new civilizations as I play them, and I'm going to start with my favorite of the new civs (so far): Assyria.

Assyria is one of the most powerful and feared civilizations of the ancient world. Their prowess on the battlefield and brutal treatment of subjugated foes made their armies so feared by rivals, that most opponents would seal themselves behind walls rather than face Assyrian armies in the open field. That is, if they didn't just surrender in exchange for leniency. Because of this, Assyria became masters of siege warfare and developed many novel tactics and inventions to assist in the storming of walls and breaking of gates. This prowess in siege is represented in Civilization V: Brave New World with both the presence of the Siege Tower unique unit, and the military experience boost given by the Royal Library unique building, as well the strong incentive that Assyrian players are given for capturing cities.

Ashurbanipal was the last significant king of the Neo-Assyrian Empire. He ruled through most of the middle of the seventh century B.C.E. Although Ashurbanipal oversaw the beginning of the decline of the Assyrian Empire, he is best known for his legendary collection of cuneiform documents that were stored in his royal palace at Nineveh.

UPDATE January 6, 2014 (8:40 pm PST):

It was brought to my attention that I had erroneously reported that Assyria could not steal technologies from City-States. This impression was based on an early attempt that I had made to capture a city state, but for which I did not receive a technology. I had assumed that City-States did not qualify because they do not progress through the technology tree in the same manner as normal civs (although they do generate science, their tech level seems to be based on the tech level of the most advanced normal civs that they have met).

Upon further testing, I confirmed that Assyria can, in fact, steal techs from City-State. I have corrected the section about the Treasures of Nineveh ability, and have updated the strategy accordingly.