The Book of DieselThe Light Before the Gospel“Narseh showed him the open hand and repeated the oath. Cyrus studied it without reverence. 'Every people says its justice is universal,' he said. 'Usually they mean everyone should obey them.' Narseh replied, 'Then judge the oath by what it forbids us to do when we are strong.'”
The Book of Diesel · Gospel Threshold Edition v4.5
Historically anchoredThe setting or public event is documented; dialogue, motives, and recurring characters are invented.
Cyrus emerged from Anshan and overthrew Astyages before founding the Achaemenid Empire; detailed private conversations are not preserved.
Narseh is fictional, and his intimacy with Cyrus is invented to humanize the decisions surrounding conquest and governance.