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Vassal State

Geopolitical framework exploring client states bound by forced loyalty oaths to an empire, driving subplots of covert underground resistance.

The thrill of a hidden war waged by spies and saboteurs, where every act of defiance is a gamble and the fate of nations hangs on whispered secrets and impossible choices.

Books

Queen of ShadowsSarah J. Maas
Kingdom of AshSarah J. Maas
The Underground RailroadColson Whitehead
An ember in the ashesSabaa Tahir
The Black PrismBrent Weeks
A Memory Called EmpireArkady Martine
The Will of the ManyJames Islington
Trickster's ChoiceTamora Pierce
InversionsIain M. Banks
City of StairsRobert Jackson Bennett
Servant of the EmpireJanny Wurts
Mistress of the EmpireJanny Wurts
The Battle of Hackham HeathJohn Flanagan
Trickster's QueenTamora Pierce
Empire in Black and GoldAdrian Tchaikovsky
Winter's OrbitEverina Maxwell
The Crimson CrownCinda Williams Chima
Fire logicLaurie J. Marks
Fear the FlamesOlivia Rose Darling
GoliathScott Westerfeld
CetagandaLois McMaster Bujold
Memory of WaterEmmi Itäranta
Star GuardAndre Norton
The UnbrokenC. L. Clark
Torch of FreedomDavid Weber
A Planet Called TreasonOrson Scott Card
Twelve Kings in SharakhaiBradley P. Beaulieu
Shadow of FreedomDavid Weber
By Heresies DistressedDavid Weber
Dragonfly FallingAdrian Tchaikovsky
DominionC. J. Sansom
JaranKate Elliott
OrcaSteven Brust
The Song RisingSamantha Shannon
Tribesmen of GorJohn Norman
The glass spareLauren DeStefano
The Scarab PathAdrian Tchaikovsky
The Blue WorldJack Vance
WorldsJoe Haldeman
In the Stormy Red SkyDavid Drake
Hidden EmpireOrson Scott Card
Araminta StationJack Vance
A Torch Against the NightSabaa Tahir
DeceiverC. J. Cherryh
PrincepsL. E. Modesitt, Jr.
WidowlandC. J. Carey
Steel TideNatalie C. Parker
Last of Her NameJessica Khoury
Beneath the CitadelDestiny Soria
When the Tide RisesDavid Drake
Lady-ProtectorL. E. Modesitt, Jr.
The Tyrant Baru CormorantSeth Dickinson
NolynMichael J. Sullivan
An Earthly CrownKate Elliott
Heart ReadersKristine Kathryn Rusch
Flames of MiraClay Harmon
Dawn StudyMaria V. Snyder
SeasparrowKristin Cashore
Cinnabar ShadowsLynn Abbey
The Revolution From RosinanteAlexis A. Gilliland

Related

ColonizedFeudalParasiticThe InterregnumAlt-HistoryMercenaryAnarchyGalactic Hegemony