To make it more sense
Endroll (true maou which has the power to "END" everything) was just chilling, he never hostile nor engaging in destructive action
It's just the GOD going apes and afraid of him (specifically END skill) and decided to kill him.... In which, God is successful in defeating him but cannot delete Endroll for good
Thus God ultimate plan begin.
God divided Endroll into smaller pieces and spread the piece in all the isekai.
Also, God take one of the piece, fused it into a human (which the Edd our MC we knew), giving it a fake memories (fake hometown), and giving Edd a hell of infinity trial loop just to broke his spirit by thinking "oh Maou is bad, let's kill him" (or rather, should I say kill his original body)
Which is why we never have Edd proper background despite him wanting to go home, it doesn't even exist afterall