The Broken Oath

by Sumiko Nakano

Edo, 1868. The empire is bleeding. So are the lies.

After killing a man they weren’t supposed to and fleeing the political firestorm in Aizu, the Hayashi sisters arrive in Edo under cover of silence. But the capital is no sanctuary. It’s a city dressed in ceremony, rotting underneath. Foreigners haunt the docks. Spies poison the palaces. And everyone smiles as they sharpen their blades.

Sumiko, Misako, and Aiko didn’t come to play diplomat. They came to uncover the truth behind their father’s death—and drag it, kicking and screaming, into the light. But truth has a price in Edo. And someone’s already decided the sisters are worth more dead than dangerous.

They carry no clan banner. No daimyō protects them. What they have are each other, a few blades, and the memory of the man whose murder was rewritten as sacrifice. Every answer leads deeper into the rot—into crumbling mansions, forbidden letters, foreign whispers, and betrayals old enough to wear new faces.

Edo stands between two one foot in feudal tradition, the other drowning in politics and guns. Honor is just a word people use when they want you to die quietly. And for women—especially armed ones—there’s no safe ground. Only expectations to break.

This is not a war of nations. It’s a war of ghosts. Of legacies. Of sisters who refuse to kneel.

The world is burning—and these women came with oil.

For readers aged 14 and up — no upper limit.
Some stories aren’t bound by numbers. They’re forged in silence, scars, and the will to endure.

465 pages, Kindle Edition

Published May 28, 2025

About the author

Sumiko Nakano writes books for readers who prefer history with mud on its boots. Her work centres on nineteenth-century Japan, particularly the Boshin War, Aizu, samurai society and the women whom conventional histories too often pushed to the edges.

The Daughters of Wars series follows sisters caught in a country tearing itself apart, combining historical detail with brutal, character-driven stories about loyalty, family, vengeance and survival. The series includes The Birth of Steel and Vengeance, The Broken Oath and The Lost Banner, alongside a mature black-and-white manga adaptation.

Her wider historical work approaches the past from different directions. The Jōshitai: Unsung Heroines of the Boshin War examines the women of Aizu. Rot Beneath the Blossoms challenges comfortable ideas about samurai mythology, propaganda and national memory, while See Then Stand: Nakano Takeko returns to one of the Boshin War’s most compelling figures through a dual-voiced historical narrative.

Not every book remains on the battlefield. Oku-Iya, or There and Back Again ventures into Japan’s remote valleys. Drive, Die, Repeat: Chaos, Castles, and OnnaMusha turns Scotland into a journey of castles, confusion and questionable decisions. SHUT UP & EAT: From Sumo Stew to Spotted Dick brings cultural memory, comfort food and a certain amount of chaos into the kitchen.

The shelves may look varied, but the instinct behind them remains the same: dig beneath the tidy version, find the human story and write it with enough force that the past refuses to sit quietly.