Captain Marcus D'Ivoire is captain of the 1st Battalion of the Colonials, the Vordanai empire's colonial garrison in a land where rebellion has suddenly exploded. His job has just become much tougher, and it's not made easier of the new colonel. Marcus, as senior captain, has been running the regiment since the death of Colonel Juarez. He's happy to be relieved of the paperwork and extra responsibility that goes along with that, but Count Colonel Janus bet Vhalnich Mieran turns out to be a very odd character indeed. He's here to put down the rebellion, but he has another mission, too, that he isn't telling anyone about.
Winter Ihernglass is a ranker in that same army. Winter's little secret is that she's a woman--she disguised herself as a man and enlisted in the Colonials to escape her past. She relies heavily on not being noticed very much. When changing conditions see her promoted first to sergeant and then to lieutenant, it's very much a mixed blessing. She needs to make herself into a leader of men and take responsibility for leading her company into battle against the rebellion.
Our main viewpoint characters are Marcus and Winter, but we do get a few scenes from the perspective of the "other side," specifically the Vordanai-trained rebel general and some Khandari priestesses.
The story itself is very effectively setting up the beginning of a multi-volume fantasy epic. It's a flintlock fantasy, with government and social institutions appropriate to that time period and technology level, and the people are humans. Other than that, nothing about the politics or culture suggests that this is in any way set on our world. The world-building is good, the characters are complex, and the religions feel real. That last point is a pet peeve of mine; too often in fantasy worlds one sees "religions" that mainly reflect the author's modern skepticism and hostility to whatever flavor of religion they were raised in, with no apparent awareness that other intelligent, honest people might think--and believe--differently, especially in a radically different environment than our present day. It's not a perfect book. There's a lot going on here and sometimes it's hard to keep up. At times, Winter's success in hiding her gender, for so long, and then when she is promoted to command of a company and the higher visibility that brings, strains credulity.
Stick with it, though. It's an enjoyable book, and rewards persistence.
I bought this audiobook.