The Fort At River's Bend by Jack Whyte

A seasoned Roman veteran leads the effort to build and defend a strategic riverside stronghold as Britons struggle to survive after Rome’s withdrawal; through engineering, training, diplomacy and hard choices he transforms a ragged band of refugees into a disciplined community capable of resisting Saxon raiders and rival warlords. The novel follows the practical challenges of fort-building, the tensions of leadership and loyalties, and the human costs of forging a fragile new order in a turbulent, post-imperial Britain.

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