Early Chinese Civilization
The story of the oracle bones of Shang is one of the most exciting in the annals of archaeology, in view of the flood of light it has shed upon the early history of China. ... Altogether 100,000 of these bones — shoulder blades of deer and oxen and the carapaces of toroises — have been unearthed and the results of research upon 15,000 of them published. The characters inscribed upon them, dating from about 1300 B.C., and some of the signs found on Yang-shao pottery represent the earliest known form of the Chinese language. Some 5,000 characters have been distinguised and 1,500 of these deciphered. A major reform of Chinese writing in the second century B.C. is the reason why the meanings of many of the older characters have been lost. [China: Its History and Culture, 14-5]

These inscriptions record the pyromantic divinations performed at the court of the last nine Shang kings. In this kind of divination, the king or his diviners would address an oral “charge,” such as “We will receive millet harvest,” to a specially prepared turtle plastron or cattle scapula while applying a hot poker or brand to produce a series of heat cracks in the shell or bone. They then interpreted these cracks as auspicious or inauspicious, and the king would deliver a prognostication, such as “Auspicious. We will receive harvest.” After the divination had taken place, engravers carved the subject of the charge, and (sometimes) the king’s forecast, and (less frequently) the result, into the surface of the shell or bone — hence the modern Chinese term jiaguwen, “writings on shell and bone.” [Sources of Chinese Tradition, 5]

The Shang Pantheon
From Divination to Sacrifice
The Shang kings lived in a world that was dominated by a complex pantheon of Powers that included: Di, the High God; Nature Powers, like the (Yellow) River, the Mountain, and Ri, the Sun; former Lords, like Wang Hai, who were apparently ex-humans whom the cultists now associated with the dynasty; pre-dynastic ancestors, like Shang Jia; dynastic ancestors, whose cult started with Da Yi and ended with the deceased father of the reigning king; and the dynastic ancestresses, the consorts of those kings on the main line of descent, who likewise received cult in the order of their husbands’ accession. [Sources of Chinese Tradition, 10.]
The Shang treated their ancestors with the kind of ritual regularity and order that they were unable to apply either to the Nature Powers or to Di himself. As ex-humans, the ancestors were approachable and comprehensible in ways that the other Powers were not. [Sources of Chinese Tradition, 14]
The general assumption that the ancestors, when properly treated, continued to smile on their living descendants is again central to much of the religion of Zhou and Han. The preference for male children — so marked in later Chinese culture and entirely comprehensible in a dynastic system in which descent passed through the male line — was already present in the Shang divinatory record. The central value of xiao or filiality” must surely have had its origins in the great reverence that the Shang paid to their ancestors — in divinatory inquiry, in cultic offerings, and in the rich furnishing of their graves. [Sources of Chinese Tradition, 22]
The power of the Shang elites depended, in part, upon their control of superior armaments like bronze dagger-axes and horse-and-chariot teams, but the true authority of the dynasty — like that of the Neolithic chieftains who had preceded them — was psychological. Their material power had to be sanctified and legitimated. Much of the elites’ legitimacy derived from their ability — through divination — to define, explain, and control reality, a reality that, in a Bronze Age theocracy, was primarily conceived in religious and familial terms. [Sources of Chinese Tradition, 16]

The following section of the “Shao Announcement” (from the Book of Documents) is supposed to record the words of the second Zhou ruler’s uncle, the Duke of Zhou, who served as regent for the young king:
Ah! August Heaven, High God [Shangdi; a.k.a. the Lord on High], has changed his principal son and has revoked the Mandate of this great state of Yin [a.k.a. Shang]. When a king receives the Mandate, without limit is the grace thereof, but also without limit is the anxiety of it. Ah! How can he fail to be reverently careful!
       Heaven has rejected and ended the Mandate of this great state of Yin. Thus, although Yin has many former wise kings in Heaven, when their successor kings and successor people undertook their Mandate, in the end wise and good men lived in misery. Knowing that they must care for and sustain their wives and children, they then called out in anguish to Heaven and fled to places where they could not be caught. Ah! Heaven too grieved for the people of all the lands, wanting, with affection, in giving its Mandate to employ those who are deeply committed. The king should have reverent care for his virtue. ... Let the king reverently function in his position; he cannot but be reverently careful of his virtue. We cannot fail to mirror ourselves in the Xia [an earlier dynasty]; also we cannot fail to mirror ourselves in the Yin. ... We must not presume to suppose that the Yin received the Mandate of Heaven for a fixed period of years; we must not presume to suppose that it was not going to continue. It was because they did not reverently care for their virtue that they early let their Mandate fall. [Sources of Chinese Tradition, 36]