The time line according to the books in the Jade Kings Library
Large amounts of Human refugee landed on the shores of Talavia. The demon armies that caused the continent to sink were lost.
The clan was looking for a new place to live when they stumbled across the cave system.
Hellduke of pride success in corrupting the humans enough that they turned against the High Elves who were helping them. The Corrupted Human Uprising caused the mistrust between the humans and elves to grow to open warfare.
2 great armies of demons came out of the portal and used this world as a battle ground.
The two demon armies destroyed each others forces. A few survivors fled to heal and wait.
A plague started killing off the dragons. Is wiped out most of the dragons. For 25 years it swept across the lands. Then it stopped. The cause is still unknown. In the dragons attempts to stop the plague the first dragonborn was birthed.
The Jade Kings bold plan to unite the dwarf and human kingdom under one rule begins with the Kings Highway. Many clans joined to start the tunneling project through the mountains.
A wizard made a pact with something to gain power. With the opening of the portal the plans changed as the wizard was backstabbed and used as a pawn.
With the rising of the Lich the dwarfs join forces to put a stop to him. the alliance building the Kings highway helped usher in a united dwarven army to fight against the undead forces of the Lich.
The Jade Kings made the nations who his Highway run through sign a treaty. It was simple and all nations agreed to the terms.
A volcano in the Eastern mountains destroyed a dwarven stronghold. The refugees of the stronghold spread across the Kings Highway. Minagar would not allow the refugees to settle on it's lands.
The two construction crews meetup for the last time. The final build is in the Elf Nation. There is a monument set at the point of the final stones laid on the ground. The day is celebrated yearly across the Highway.