The Guardsman: Book 1: Honor of the Fallen:

A lone man who carries the name of the Empire's ultimate shame and anonymity, 'John Smith'. Stripped of everything from his past, cast out and stumbling through the world he sees everything he grew up believing with new eyes. The harsh realities of his world nip at his flanks and heels every day of his new life, while memories and painful traumas of his old life plague his days and even nights.
The true price and cause of his silent suffering and banishment are a secret he refuses to speak. ...