Era beginning/end
Humanoids rose up to destroy the Elder Dragons.
This event was the first recorded time that all Humanoid species rose up for the same cause. The blossoming civilizations were done with the tyrannical rule of the Elder Dragons. When the smoke cleared, the ground was soaked with the blood of thousands. Very few Elders remained, these were to oldest and wisest; they hid from the fight. The humanoids deemed them as non-threating because of their lack of numbers.