Of the immediate successors of Nimrod we have no account that even the most lenient criticism can view as historical.  It appears that his conquest was followed rapidly by a Semitic emigration from the country—­an emigration which took a northerly direction.  The Assyrians withdrew from Babylonia, which they still always regarded as their parent land, and, occupying the upper or non-alluvial portion of the Mesopotamian plain, commenced the building of great cities in a tract upon the middle Tigris.  The Phoenicians removed from the shores of the Persian Gulf, and, journeying towards the northwest, formed settlements upon the coast of Canaan, where they became a rich and prosperous people.  The family of Abraham, and probably other Aramaean families, ascended the Euphrates, withdrawing from a yoke which was oppressive, or at any rate unpleasant.  Abundant room was thus made for the Cushite immigrants, who rapidly established their preponderance over the whole of the southern region.  As war ceased to be the necessary daily occupation of the newcomers, civilization and the arts of life began to appear.  The reign of the “Hunter” was followed, after no long time, by that of the “Builder.”  A monumental king, whose name is read doubtfully as Urkham or Urukh, belongs almost certainly to this early dynasty, and may be placed next in succession, though at what interval we cannot say, to Nimrod.  He is beyond question the earliest Chaldaean monarch of whom any remains have been obtained in the country.  Not only are his bricks found in a lower position than any others, at the very foundations of buildings, but they are of a rude and coarse make, and the inscriptions upon them contrast most remarkably, in the simplicity of the style of writing used and in their general archaic type, with the elaborate and often complicated symbols of the later monarchs.  The style of Urukh’s buildings is also primitive and simple in the extreme; his bricks are of many sizes, and ill fitted together; he belongs to a time when even the baking of bricks seems to have been comparatively rare, for sometimes he employs only the sun-dried material; and he is altogether unacquainted with the use of lime mortar, for which his substitute is moist mud, or else bitumen.  There can be little doubt that he stands at the head of the present series of monumental kings, another of whom probably reigned as early as B.C. 2286.  As he was succeeded by a son, whose reign seems to have been of the average length, we must place his accession at least as early as B.C. 2326.  Possibly it may have fallen a century earlier.