After the Fall (Roman Time Travel 2nd Edition ) by Morgan O’Neill
War is threatening and this time around, Gigi Perrin (the traveler) together with her husband Quintus Magnus (the Roman Warrior) allied with the Visigoth King Alaric march on Rome. From a distance, there waits Princess Galla Placidia, the admirable sister of the detestable Emperor Honorius.
Though she is in fear, she stands put to defend the Roman country from a terrible invasion. Placidia decides to meet Alaric’s delegation in an attempt to save her country. Once she met the Visigoth Prince, Athaulf, who is the second in command, the overwhelming passion between them sparks off a forbidden love.