Rebirth: Book One in the Circle of Fire by Nick Kyme
Fiv years have passed since war came to Nocturne. Third Company, still feeling its losses, recovers its strength. And though a small party have ventured out in search of a certain errant fire-born, it is the Salamanders of Fifth Company who must wage war. On Helentine, the Black Legion has come in the name of Chaos an only Brother-Captain Drakgaard's warriors stand in the way of their dark glory. Victory for the Imperium hings on the alliance between the Salamanders and the Sisters of the Ebon Chalice, warrior zealots and devout servants of the Ecclesiarchy. But there is more to this Promethean War than conquest, and only as the conflict grinds on are the true motives of the enemy revealed...