The mighty King Miotis came down to Earth to recapture his lost desire for war. But what he saw on this planet, caused him to feel differently.
Stanton shook his head hard. "No!" his voice thundered, and sent echoes answering from the walls. "No! I will never draw a blade against even a rat. The old races had their sayings--one I remember well--'Live and let live.'"
"Good-bye, then, Bly Stanton," Hays said. "And good luck."
Bly Stanton did not turn as he clambered over the rock ramparts. And after a while the night hid him in its sable fold.
The man climbed the last ridge of the giant sand dune and looked down at a setting moon sending a long slanting fan of silver over an immense lake. He had seen the lake many years before, had almost forgotten its existence so long ago had it been.
He turned and looked at the ruins, rising pyramid-like from the tree line to the north. Chicago had been the name of a vast city which had existed here. There had been other cities as large, and some larger. From the deepest recesses of his mind, Stanton remembered an almost forgotten fact. There had been more than
A warrior king finds his subjects and all the enemy worlds that used to oppose him have all lost taste for war. His advisor shoots his soul across the universe to Earth, where war is still popular. In the post-atomic war world people hack at each other with swords, which suits him fine.
The story doesn't really go into the reasons for fighting or the reasons for peace; people are just magically agressive or peaceful. Quite a lot of the story is unexplained (where did the women come from?) so it's really more of a fantasy story than sci-fi.