Literature: Time Lag

"Time Lag" is a short story by Poul Anderson.

On the planet Vaynamo, Elva is completing her circuit as the representative of her husband the Freeholder when their holding is attacked. She manages to get her infant son to an Alfavala — one of the marginally intelligent aliens of this planet — but her husband is killed, and she, taken captive. The fleet commander takes her as his concubine, and she tries to use the position to her best advantage, learning of how his overpopulated planet, Chertkoi, is conquering others for resources, despite using a slower-than-light travel (with dilation).