"Time Lag" is a short story by PoulAnderson.

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).

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!!Tropes
* {{Arcadia}}: Vaynamo, rural, peaceful, and happy.
* BittersweetEnding: Elva loses a lot
* BlueBlood: Elva and her husband hold some hereditary position
* DamselOutOfDistress: Elva never fights, but her resistance is unending.
* DeadGuyJunior: Elva learns of one at the end
* DisproportionateRetribution: The attack at the beginning is one of several, to wipe out villages because the planet resisted.
* DoWithHimAsYouWill: Elva is offered this at the end.
* TheEmpire: Chertkoi has conquered many planets already.
* EvilCannotComprehendGood: Why not just dispossess to Alfavala?
* FeudalFuture: since it's hereditary
* FishOutOfTemporalWater: Her rescuers quickly assure her that she's welcome, even though she's now younger than her own son.
* HappilyMarried: Elva in the opening
* HappinessInSlavery: Elva convinces Bors she is this
* HookedUpAfterwards: One fellow prisoner hopes she will let him visit at the end.
* LukeYouAreMyFather: In "Time Lag", Elva is told by another of her rescuers that one of them is her grandson; then he immediately takes her hands.
* MoralMyopia: Chertkoi, apparently. Bors embodies it, not even comprehending resistance.
* MosesInTheBullrushes: Elva in "Time Lag" sends off her son from the attack.
* NonIdleRich: Elva and her husband.
* PeopleOfHairColor: Vaynamo is inhabited by blue-eyed blonds -- with slanted eyes, to tweak the PhenotypeStereotype.
* PopulationControl: Vaynamo has stablized its population; Chertkoi regards them as hoarding resources.
* RockBeatsLaser: Defeat by the rural Vaynamo, lacking in industry, astounds Chertkoi
* SexSlave: Elva is picked out as a concubine in "Time Lag"
* ServantRace: The Alfavala have chosen this role
* ThickerThanWater: Elva is told at the end about how her son survived, and has descendents, so that she is not alone.
* TimeDilation: Elva ends up only a few years older, while her infant son is now old, and indeed, has an infant grandson.
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