The last of the great kings of Assyria (668-627 BC), who established the first systematically organized library in the ancient Middle East, a huge collection of Assyrian clay tablets in his palace and that of his grandfather, Sennacherib. The library has been extremely valuable in revealing the art, science, and religion of ancient Mesopotamia. Approximately 20,720 tablets and fragments have been preserved in the British Museum. This collection was assembled by royal command, whereby scribes searched for and collected or copied texts of every genre from temple libraries. Theses were added to a core collection of tablets from Ashur, Calah, and Nineveh itself. The major group includes omen texts based on observations of events; on the behavior and features of men, animals, and plants; and on the motions of the Sun, Moon, planets, and stars. There were dictionaries of Sumerian, Akkadian, and other words, all important to the scribal educational system. Ashurbanipal also collected many incantations, prayers, rituals, fables, proverbs, and other "canonical" and "extracanonical" texts. The traditional Mesopotamian epics - such as the stories of Creation Gilgamesh Irra Etana and Anzu - have survived mainly due to their preservation in Ashurbanipal's library. Handbooks scientific texts and some folk tales show that this library of which only a fraction of the clay tablets has survived was more than a mere reference library. His many brilliant military campaigns served only to hold what had been already won by previous kings though Egypt regained its independence and Elam was only retained by complete devastation.