Ash - Mary Gentle

In a world not unlike fiteenth century mediaeval Europe . . .
For the beautiful young woman Ash, life has always been arquebuses and artillery, swords and armour and the true horrors of hand-to-hand combat. War is her job. She has fought her way to the command of a mercenary company, and on her unlikely shoulders lies the destiny of a Europe threatened by the depredations of an Infidel army more terrible than any nightmare.
Ash is guided by voices. They may come from her God, or from a source infinitely stranger . . .
ASH: A SECRET HISTORY marks the full-flowering of the talent of one of the world?s most acclaimed writers of fantasy.