The Samurai by Shūsaku Endō

A low-ranking samurai is sent as an attendant on a diplomatic voyage to New Spain and Europe, where encounters with strange customs, moral ambiguities, and shifting loyalties force him to confront his own sense of duty and faith; the narrative quietly examines cultural dislocation, the clash between personal conscience and social obligation, and the human costs of historical change as he returns to a Japan that has moved on.

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