The Bellica Trilogy by Katje van Loon.
Prophecy. Calamity. Faith.
Leader of the Thirteenth Regiment, protector of Athering, and spouse of a good man, Bellica Agate has simple goals—peace and privacy. War with neighboring Ixtepan threatens every part of her world; yet she must act, her every step haunted by dusty prophecies that foretell the coming of one who will save Ixtepan and end the bloodshed.
Who is Sho-qoot-Bak? Will she appear before Athering and Ixtepan rip the world asunder?
The voice of a goddess whispers in Agate’s ear: You cannot escape what you were born to do. Every step of the perilous journey moves Agate closer to a fearsome truth: she must face her past to save the future. The price of peace is courage.
The gods demand blood. Hers.