This article reexamines the hypotheses of Guo Moruo and H.G. Creel that Shang Di was the high god of the Shang and Tian, that of the Zhou. It proposes that Shang Di was originally the spirit of the pole star. As such, it was the one celestial body which was higher than the ten suns, with whom the Shang ancestors were identified. Tian was not a high god, but quite literally, the sky. The sky was the location of the Shang Di and the other ancestral spirits, so it came to serve as a euphemism for Shang Di or, more broadly, for Shang Di and all the celestial phenomena and spirits who were under his aegis. The primary distinction between the Shang and Zhou was not that Shang Di was particular to the Shang, but that the Shang rulers identified themselves with the ten suns. Shang Di, as the pole star, was acknowledged by both Shang and Zhou as the highest of the spirits. Tian, as the sky, was understood primarily as the celestial bodies that inhabit it. As in later time, the sky was a spiritual force associated with patterns of time, which were revealed in the movements of the celestial bodies. Thus, the original tian ming (“celestial mandate” or “mandate of heaven”) was, quite literally, an astronomical sign, a “command” seen in the sky during the reign of Wen, whose son Wu founded the Zhou Dynasty.