In many human societies of the past, knowledge and beliefs relating to the sky served to reinforce the political status quo. In some cases, the power of the ruler was directly linked to the sky or to sky gods in the form of celestial objects. Thus Old Kingdom Egyptian pharaohs’ power depended upon sun worship, as did that of the ruling elite of the Inca empire and that of Roman emperors at the time when Mithraism held sway. Chinese emperors, on the other hand, established their place at the head of the political order by analogy to the north celestial pole—the hub of the turning sky—and underpinned this by aligning the buildings of the Imperial Palace (Forbidden City) along the meridian. The layout of the greatest medieval Hindu city, Vijayanagara, together with its position in the landscape in relation to sacred hills, helped to establish the place of its kings within the cosmic order. Similarly, the sarsen monument at Stonehenge, undoubtedly a potent symbol of the power of the chiefs who controlled it, incorporated a solstitial alignment that, by linking the monument to the workings of the cosmos, may have contributed to its symbolic power every bit as much as the exotic stones and the scale of its construction.
Considerable social prestige and political power could accrue to anyone who was seen as able to control or influence phenomena that could not be controlled by anyone else. For this reason, an astronomer-priest might hold the solstice ceremony around the time that the sun set in a particular horizon notch so that he could demonstrate the power of “turning it around.” Alignments that “worked” only at special times—the appearance of the midsummer full moon low over the recumbent stone of a Scottish recumbent stone circle, for example, or the sudden entry of sunlight into places that were normally dark, such as the cave below the zenith tube at Xochicalco in Mexico— would have been highly impressive and could have been used to help justify the power and prestige of the priest in command. Such apparent control ultimately relies, of course, on the regularity of astronomical phenomena—reliable cycles that are tied to other, observable events in the natural world.
Where a priest or shaman professed the ability to predict phenomena such as eclipses or the appearance of comets, the results (as we know) would be a lot more unreliable. Indeed, unexpected events would undermine their authority and could even cause social and political instability. Certainly they were commonly taken as bad omens. In c.e. 549, an unexpected lunar eclipse led two Teutonic armies to flee the scene of battle and thus postponed the Roman occupation of the Carpathian basin by two years. The appearance of Halley’s Comet in the spring of 1066 portended disaster for King Harold at the battle of Hastings. And a spectacular meteor seen in the Aztec capital of Tenochtitlan around 1515 caused great fear among the people. The Spanish conquest followed just a few years later.
Observations of the regular cycles of the skies had a clear practical value within a wide variety of human societies in the past by helping to keep subsistence activities in step with the seasonal cycles of nature. However, as often as not—and especially within larger political units with strong and powerful social hierarchies—they also played a significant role in perpetuating the power of the ruling elites.
