John Stack

Atticus is the young captain of Aquila, the flagship of the attack fleet of the Roman navy. He finds himself in conflict with his inexperienced commander and sails into a carefully-laid trap.  Book 2 of series.

Atticus is the commander of the Roman navy, blockading a port near Tunis, when the Roman legions are defeated by the Carthaginian army. He and his ships escape the skilful Carthaginians but are then almost completely annihilated by a terrible storm.  Book 3 of series.

Masters of the Sea, v1; Atticus is captain of one of the ships of Rome's small, coastal fleet and Septimus, a legionary commander from Rome. Can Atticus, and the fledgling Roman navy, out-wit and out-fight his strength.  Book 1 of series.