B.R. Stateham 
Death by Greek Fire [EPUB ebook] 

After twenty years as a professional soldier, Decimus Julius Virilis – distant kin to the Imperator himself – has been commissioned the third in command of the newly formed Legio XII Brundisium.
It’s his last assignment before retiring from Caesar Augustus’ legions – and turns out to be much more dangerous than he anticipated. After being shipped off to Dalmatia to fight the rebels waging war against Rome, the untrained legion immediately blunders into a death trap deep in enemy territory, leaving the commanding officer and his lieutenants dead.
Decimus is commanded by the heir apparent, Tiberius Caesar, to find the mastermind who planned the diabolical trap and is attempting to plunge the Roman Empire back into a civil war. But can the Roman tribune see the unseen and solve a crime others think is impossible?
Set in the time of the Roman Empire, Death By Greek Fire is the first book in B.R. Stateham’s ‘Decimus Julius Virilis’ series of historical mystery novels.