The Golden Era started after the first member of a Red Lizards clan gain wings when reaching the Sky Realm and becoming the first member of the Dragon Race.
Because they were an evolved race, the dragons were stronger, faster, and more resistant than other races. Also, their children are already born with wings and a soul much more powerful than the usual.
Then their people quickly overcome other races as they colonized entire worlds and became the most powerful race in the universe. But they were not really united, and each Clan had its own objective goals.
After more than a thousand years without a united leadership, the first Dragon Emperor appeared. He had enough power and leadership skills to unite the Dragon Clans and created the Tiankong Dynasty, also known as the Royal Dragon Clan.
Sorry for the delay in posting again; I'm having issues with WN staff due to unfair treatment (again).