There were, first of all, at either end of it, north-east and south-west, the two great empires of ASSYRIA and EGYPT, in many respects wonderful counterparts of each other. No one will understand the history of Palestine, who has not grasped its geographical position relative to these similar empires. Syria, shut up between the Mediterranean sea and the Arabian desert, has its outlets north and south into two great river-plains, each of them ending in a delta. Territories of that kind exert a double force on the world with which they are connected, now drawing across their boundaries the hungry races of neighbouring highlands and deserts, and again sending them forth, compact and resistless armies. This double action summarises the histories of both Egypt and Assyria from the earliest times to the period which we are now treating, and was the cause of the constant circulation, by which, as the Bible bears witness, the life of Syria was stirred from the Tower of Babel downwards. Mesopotamia and the Nile valley drew races as beggars to their rich pasture grounds, only to send them forth in subsequent centuries as conquerors. The century of Isaiah fell in a period of forward movement. Assyria and Egypt were afraid to leave each other in peace; and the wealth of Phœnicia, grown large enough to excite their cupidity, lay between them. In each of these empires, however, there was something to hamper this aggressive impulse. Neither Assyria nor Egypt was a homogeneous State. The valleys of the Euphrates and the Nile were, each of them the home of two nations. Beside Assyria lay Babylonia, once Assyria's mistress, and now of all the Assyrian provinces by far the hardest to hold in subjection, although it lay the nearest to home. In Isaiah's time, when an Assyrian monarch is unable to come into Palestine, Babylon is generally the reason; and it is by intriguing with Babylon that a king of Judah attempts to keep Assyria away from his own neighbourhood. But Babylon only delayed the Assyrian conquest. In Egypt, on the other hand, power was more equally balanced between the hardier people up the Nile and the wealthier people down the Nile--between the Ethiopians and the Egyptians proper. It was the repeated and undecisive contests between these two during the whole of Isaiah's day, which kept Egypt from being an effective force in the politics of Western Asia. In Isaiah's day no Egyptian army advanced more than a few leagues beyond its own frontier.