4000 BCE (approximate): The first expeditions from the Omega Sector arrive at Earth and begin to investigate the planet as a potential candidate for colonization. Using early population centers as bases of operation, these travelers explore and catalogue Earth’s ecology and make a detailed survey of the planet, perhaps lasting decades.
Over time, the natives grow less and less receptive to the actions of these gods and the terrible beasts that serve them. It is believed that the first heroes rise up during this time, taking psychic control of some Omega Sector devices, called “Star Chariots” and driving the creatures out. Verified Omega Sector bases from this period have been found in the Yangtze Delta, Ganges Valley, Mesopotamia, the Nile Delta, the island of Britain, the Mississippi Valley, Central America and along the west coast of South America.
In the wake of this temporary occupation, Earthlings rapidly gather in larger settlements than before, build large structures to commemorate (and later store) the large devices used by the heroes to repel the invaders, and develop a consuming interest in astronomy, to watch for future incursions. Over the centuries, these events become more legend and less fact and form the basis for the earliest hero tales such as the epic of Gilgamesh.
As soon as the menace had passed however, the heroes lost the ability to summon their great weapons, which seemed to respond to the presence of the Omega Taskmasters who had created them. The people they had saved did not know this however and many of the heroes raised themselves up as king, using threats of divine retribution to build mighty empires for themselves.
A select group of priests knows the truth and preserves it within their sect, even as kings descended from the great heroes of old come to believe the stories of “star chariots” and monsters descending from the heavens to be old wives’ tales. These priests watch the skies obsessively from their temples, waiting for any sign of the beasts’ return.
4000-2100 BCE (approximate): “Three Sovereigns and Five Emperors” era of Chinese pre-history. These eight rulers, wise and long-lived, use the power of the Star Chariot dubbed Emperor Yao to impose peace and stability on China. Their contemporaries called them the August Ones or “supreme beings”. Modern scholars tend to translate their titles as “king” or “sovereign”.
2100-1600 BCE: Breaking the tradition of his eight predecessors, Chinese Emperor Yu does not leave power to the most worthy. Instead he founds a dynasty by passing power on to his son. This leads to corruption and devastation.