Rhea Silvia, spirited princess of Alba Longa and daughter of King Numitor, always had a wild streak in her, especially when compared to her demure and beautiful cousin, Antho, who was also her best friend. The pair were thick as thieves and always there for each other, especially during family tragedies, such as the deaths of Rhea's mother, Queen Jocasta, and her eldest brother, Lausus, both of whom succumbed to a deadly illness. King Numitor relies heavily on his closest advisor and younger brother, Amulius, but when tragedy strikes Aegestus, his last remaining son, on a hunting trip, Numitor slips into a deep depression.
Meanwhile, during the Latin Festival, Rhea spies a large black wolf who later reveals himself to be Mars, the god of war himself. The pair share a passionate kiss and Rhea hopes to see him again. However, her father is in a tailspin due to her brother's death, with Numitor losing himself in a deep cup of wine spiked with the milk of the poppy to dull his pain. Furthermore, Amulius convinces Numitor to hand over the throne to him, and just like that, Rhea's world is flipped on end.
While it's bad enough her father has let the kingdom slip from his grasp, he can't even stand up for his only remaining child when Amulius announces that Rhea is to become a Vestal Virgin, which will ensure she never spawns an heir who could challenge the throne. However, with the help of Antho and Leandros, the Royal Guard Antho has fallen in love with, Rhea and Mars are able to share a passionate night at the sacred lake where she is supposed to be preparing for her vows. At least she will have those memories to comfort her during the lonely nights at the House of the Vestals.
Fast-forward through months of loneliness and abuse at the hands of a certain Vestal when Rhea's pregnancy is discovered, and she is handed down a terrible punishment for breaking her vows, only to escape her tomb by Mars' hand. However, her uncle will stop at nothing to find her and extinguish any heir she might have. A series of hideous occurrences leave Rhea clinging to life, her twin newborn boys, Canus and Viridis, having been ripped from her arms and sent to their deaths down the River Tiber. Yet it seems the gods are never too far from Rhea Silvia and, once again, they intervene. Rhea will survive, but only as a wolf, and she can only take her human form once per month for the next 20 years, her wolf form's lifespan. Rhea takes the deal and exacts a smidgen of vengeance, with the hopes of one day making her uncle pay for his treachery.
Fortunately, her baby boys are rescued from the Tiber by a kind, childless shepherd named Faustulus, whose wife, Laurentia is overjoyed to take in the babies and raise them as their own, naming them Romulus and Remus. Oddly enough, a female wolf is always lurking about, watching everything they do, and over the years, she becomes the guardian of her community, the Seven Hills. Although she is only a human woman one day per month, she spends much of her time with the god of the River Tiber, Tiberinus, whom she met years ago and who had a hand in the rescue of her newborns. While he isn't as flashy as Mars, there is something to be said for his stability, kindness and loyalty. Plus, he knows her dark and tumultuous story, so there's a comfort in that.
Meanwhile, the more things change, the more they stay the same, and eventually, King Amulius' greedy reach will begin to affect the Seven Hills and her shepherds, including Rhea's sons. Rhea must use this opportunity to not only unite the community against Amulius, but rescue one of her boys, and if she is finally able to exact her perfect revenge, then so much the better.
There's a lot more that happens in this book, but I've hit the high points so as not to reveal too much. I greatly enjoyed Mother of Rome and I read it right after reading Horses of Fire and Daughters of Bronze, which was just perfect. Reading the duology of the Trojan War from the perspective of Troy's women was a perfect setup for a story about a female descendant of Troy. I highly recommend reading them in this order for maximum enjoyment.