The Dark Age
From Destiny 1 Wiki
The Dark Age is the period that followed the Collapse when the Golden Age ended. According to Lakshmi-2, "a thousand kings" rose and fell during this age. It is followed by the City Age.
The Dark Age was a time of vast suffering and terrible evil. Many survivors formed colonies in the wilderness in a desperate attempt to survive. Colonies tended not to last long from either alien hordes or infighting. Humanity was on the fringe of extinction. But out of it, the Awoken emerged, and the Exo appeared from the ruins with their memories broken. Furthermore, the Ghosts had begun looking for their Guardians, and rumours circulated of the haven beneath the Traveler that would one day become the City.