Night's Acolyte - Aether Vitalis

All vampires start out as mortals. Gabriel Chapel was no different. Gaul, 78 BC. When a chance misstep leaves him on the road after dark, Gabrielus Avidiacus wants nothing more than to get safely home to his wife and children. Instead, he is attacked by a blood-drinking demon and brutally transformed. Left to fend for himself, Gabrielus has no idea what he has become. Just one thing is clear: the only way to protect his family now is to get as far away from them as he can.
That, and kill the demon who did this to him. As he struggles to discover more about his demonic nature and the bloodlust that now rules him, Gabrielus also seeks a higher purpose to his new life. What he finds will set him on the path to becoming one of the most successful vampires the world has ever known.