For nearly a thousand years, from the formation of the great Assyrian empire to the death of Darius Codomannus, Western Asia, from the Mediterranean to Affghanistan, or even to India, had been united tinder one head, had acknowledged one sovereign.

Assyria, Media, Persia, had successively held the position of dominant power; and the last of the three had given union, and consequently peace, to a wider stretch of country and a vaster diversity of peoples than either of her predecessors.

Under the mild yoke of the Achaemenian princes had been held together for two centuries, not only all the nations of Western Asia, from the Indian and Thibetan deserts to the AEgean and the Mediterranean, but a great part of Africa also, that is to say, Egypt, north-eastern Libya, and the Greek settlements of Cyrene and Barca.

The practical effect of the conquests of Alexander was to break up this unity, to introduce in the place of a single consolidated empire a multitude of separate and contending kingdoms.

The result was thus the direct opposite of the great conqueror's design, and forms a remarkable instance of the contradiction which so often subsists between the propositions of man and the dispositions of an overruling Providence.
The struggle for power which broke out almost immediately after his death among the successors of Alexander may be regarded as having been brought to a close by the battle of Ipsus.