The Chaldeans near Ur were among the most advanced of the eastern Semites.  The Chaldeans were among the first to abandon the sacrificing of humans for ordinary occasions, substituting therefor animals. 
The Chaldean tribes recognized the right of a wife to impose a premarital pledge upon her spouse not to take a second wife or concubine; both the Greeks and the Romans favored monogamous marriage. 
They were star cultists and considered themselves to be the children of the sky father and the earth mother. The Chaldeans put the sun in the center of “the seven circles of the universe.” Also looked upon the stars as the cause of suffering.