Sword Worlds

From the publisher website: This book examines how the worlds of the Confederation interact with one another, and how a technologically outmatched people have managed to stave off Imperial dominance for so long. Their armed forces are technologically simple yet incredibly resilient; their navy is very different to that of the Imperium. Minelayers, torpedo boats and orbital defence platforms defend the home worlds whilst battlecruisers raid deep into enemy territory.