The Second Colonial era, despite the name, was in many ways nothing like the First Colonial Era. The colonies did restore their borders to an extent, but they would never reach the level they had been at previously. A large portion in the middle of the continent, particularly in Tai'Un, was left entirely untouched, perhaps out of reverence for the fallen empire or simply out of fear it would rise once more.
The slow, careful process of regaining territory began in 496 with the formal founding of Scila. This would bring on a new wave of cities, humorously referred to often as the "colonies of colonies". Whether they be break-offs from colonies that had been entirely destroyed during the early Apocalypse's Edge or new cities altogether, they differed wildly from their older counterparts.
Many of these colonies began to experiment with forms of government previously unseen before in Tellia. For example, with the population holding such an inherent distrust in any sort of absolute monarch, Latisc found itself as a republic. Despite the unimaginable power of controlling such a resource rich continent for themselves, it seemed as if Tellia had grown fearful of power itself. Most colonies would keep to themselves, fiercely fearful from outsiders that had not been vetted.
From 448 B.F to 221 B.F., this would largely remain be the state of affairs. Conflicts would arise between neighboring, smaller cities that would never grow beyond their limited scope. The larger colonies might intervene, but never to the point of staging any sort of proxy war.
In 221 B.F., however, the very first cracks in the Second Colonial Eras mutually assured destruction began to show. Aurikya fractured into several warring factions, each of which claimed their ruler as absolute. Similarly, in 193 B.F., the Glistening Plains, which was holding onto an atypical period of relative peace, erupted fiercely back into petty resource conflicts. This backslide into barbarism only seemed to be worsening as cities grew and needed more mouths to feed.
From 200 to 43 B.F., it seemed as if the elimination of the Waste Lords only put off the continents inevitable rot. Tensions between the tribes and the colonies were no better than they had been before, and it seemed as if any day that all out war would break out between them. The few kingdoms that did not outright get physically destroyed were all but entirely mentally broken. New oracles and prophets declared the end times were upon them, and the larger colonies acted in a way to indicate they believed them.
In 23 B.F., in the midst of what looked to be the end of the world, the people of Jailur would notice that the creatures of the Rot which had been terrorizing their forests suddenly disappeared overnight. While some took this as absolute confirmation of the end times, others took this to mean that The Rot itself was dead. Ergo, one of the Old Gods had died. Presumably, as the Voyager descended upon Jailur and crushed the city over the course of a week, The Rot had been slain by man.
This provided the desperate colonies and tribes with one thing if nothing else: a common enemy. Campaigns against the Old Gods sprung up anywhere that still had a functional military. Of course, this would only seem to enrage the Old Gods further, which would in turn provoke more cities up in arms against them. However, if this really were to be the end of the world, and everyone would face the same fate as Cassian Tellion remained to be seen.
In 21 B.F., with the entire world watching in horror and anticipation, Valgos Firmean of the Light's Fist would kill a God. In the aftermath of The Overseer's death, eyewitnesses would remark that he had simply disappeared in a burst of light, along with the remains of the Overseer. While it would be another 130 years before his fate would be known, this event would act as the greatest rallying cry for humanity possible. The ensuing events and battles against the Old Gods would come to be known as the War in Heaven.
According to historical reports from this time, The Voyager would be slain in 19 B.F., the Tinkerer in 15 B.F., the Broodmother in 12 B.F., and the Archivist in 5 B.F. Both the Keeper and the Leviathan are said to have been slain around the same time, but the dates of their exact deaths are uncertain. Broadly, however, it is certain they were dead by 1 B.F., marking the end of the Second Colonial Era.