Millenium World Saga: What happened in the original past?

[withheldforprivacy]

After Thief King was defeated by the priests, Zork turned him into sand, interfrering with the events. So, what happened in the original
past after that point?

 

[Papasmurf]

Wasn't it stated that the thief's soul was inside the Millennium Ring? I presume that when Akhenadin arrived and deemed Bakura useless, he tried desperately with his remaining monsters (after Diabound was blown up) to get Atem and the priests to back away before being forced to seal himself in the Ring while Zorc-Akhenadin seized the items and revived Zorc

 

[Papasmurf]

Burp

 

[Fantastische Hure]

Who even is the thief? Just a random evil person who lived in Egypt? Or some kind-of evil spirit incarnate?