The Assyrians began to expand to the west in the early part of the ninth century B.C.; by 859 they had reached the Mediter- ranean Sea, where they occupied Phoenician cities. Damascus and Babylon fell to the next generations of Assyrian rulers. During the eighth century B.C., the Assyrians' control over their empire appeared tenuous, but Tiglath-Pileser III seized the throne and rapidly subdued Assyria's neighbors, captured Syria, and crowned himself king of Babylon. He developed a highly proficient war machine by creating a permanent standing army under the adminis- tration of a well-organized bureaucracy. Sennacherib built a new capital, Nineveh, on the Tigris River, destroyed Babylon (where citizens had risen in revolt), and made Judah a vassal state.

In 612 B.C., revolts of subject peoples combined with the allied forces of two new kingdoms, those of the Medes and the Chaldeans (Neo-Babylonians), effectively to extinguish Assyrian power. Nineveh was razed. The hatred that the Assyrians inspired, particularly for their policy of wholesale resettlement of subject peoples, was sufficiently great to ensure that few traces of Assyrian rule remained two years later. The Assyrians had used the visual arts to depict their many conquests, and Assyrian friezes, executed in minute detail, continue to be the best artifacts of Assyrian civilization.

The Chaldeans became heir to Assyrian power in 612 B.C., and they conquered formerly Assyrian-held lands in Syria and Palestine. King Nebuchadnezzar (605-562 B.C.) conquered the kingdom of Judah, and he destroyed Jerusalem in 586 B.C. Conscious of their ancient past, the Chaldeans sought to reestablish Babylon as the most magnificent city of the Near East. It was during the Chaldean period that the Hanging Gardens of Babylon, famed as one of the Seven Wonders of the Ancient World, were created. Because of an estrangement of the priesthood from the king, however, the monarchy was severely weakened, and it was unable to withstand the rising power of Achaemenid Iran. In 539 B.C., Babylon fell to Cyrus the Great (550-530 B.C.).