Irregular Beast Master

What would you do when you're witnessing you world getting destroyed by the first inhabitants of the world? Would you run? But where would you run? Would you hide? But where would you hide? The First Inhabitants of the world are extremely power that even the [World Powers] are having a hard time defeating them. ...What would you do? You're the only hope. As the greatest Historian, who writes the events of the past, how would you react and write the present? His name is Marquis, the Head of the Historical Society of Figures, Science, Magics, and Continents. Using the old books from the archives, the other historians along with other magician used their life force to perform a ritual to turn Maquis to the past and correct everything and stop the catastrophe. The ritual was successful. He was reincarnated as a son of one of the most power family in the world. [Heraldgon Family] A family of fierce and powerful warrior. And the main Bloodline is known as the tamer of Dragons. Known across the entire connected Continents. As a historian, he writes the events of the past, not even the entirety of the History Office , no one knows who or what unleased the sleeping inhabitants of the world. But he has no choice but to investigate, so he can stop the chaos in the future.