The Ashurbanipal reference article from the English Wikipedia on 24-Apr-2004
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Ashurbanipal

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Ashurbanipal, or Assurbanipal, (reigned 668 - 627 BCE), the son of Esarhaddon and Naqi'a-Zakutu, was the last great king of ancient Assyria. He is famous as one of the few kings who could himself read and write. Assyrian sculture reached its apogee under his rule (Northern palace and south-western palace at Niniveh, battle of Ulai).

He assembled at Ninevah "the first systematically collected library." A library, in Oppenheim's view, apparently, was distinct from an archive: earlier repositories of documents had accumulated passively, in the course of administrative routine. Tablets from the library of Ninevah preserve the most complete source for the Sumerian/Babylonian Epic of Gilgamesh. Other sets of tablets offer what is essentially a Sumerian/Akkadian dictionary. There are arcane astronomical/astrological texts. By far the largest group of tablets (almost all of which are in the British Museum, London) however, are 'omen' texts that taught the scribes how to recognize the significance of portents.

Assurbanipal only became crown prince in 672, when Esarhaddon's oldest son Sin-iddina-apla died. Assurbanipal was very unpopular with the court and the priesthood. Contracts were made with leading Assyrians, members of the Royal family and foreign rulers to assure their loyalty to the crown prince. But it was only the energy of his mother Naqi'a-Zakutu that assured his ascent to the trone when Esarhaddon suddenly died during his Egyption campaign.

Ashurbanipal's reign, like that of most Assyrain kings was marked by incessant warfare. He began by making war on his brother Shamash-shum-ukin, who had been installed as king in Babylon; Ashurbanipal conquered Babylon and destroyed it. Oppenheim notes the curious break in all documentation during the final decade of his rule.

Oppenheim's dates for Ashurbanipal (as given here) are drawn from references in the inscription of the mother of Nabonidus. The date of his death is not known with certainty, the last tablet to mention his name is a rivate contract from Nippur dated to 631, the 38th year of his rule. Other texts say that he ruled 42 years, that is, till 627/626).

Reference

A. Leo Oppenheim, Ancient Mesopotamia: portrait of a dead civilization.