This series just gets better and better. In 'An Autumn War', we have moved on another fifteen years or so, and for the first time the shadowy threat of the Galts, seemingly behind every conspiracy in the previous books, moves out into the open, with an audacious plan - no less than to destroy the andat altogether, and then destroy the Khaiem and their poets before they have time to create more.
But although war is the main story, the underlying themes are far more intimate - family, sons and daughters, love and friendship, and the mistakes people make. Abraham's world is populated by people who are not heroes, who are not even very good at what they do, sometimes. They do the right thing for the wrong reasons, the wrong thing for the right reasons, and even the wrong thing for the wrong reasons, but we always understand why and sympathise with them.
The complicated relationship between Otah, Maati and Liat now comes back to haunt them in the shape of Liat's son, believed to be Maati's but now obvious to everyone as Otah's. This is a problem, since the two legitimate sons of a Khai are required to attempt to kill each other to secure the throne. But the quiet way everyone manages this potential difficulty, without Nayiit himself ever knowing, is very moving.
There is also a compelling side story in the shape of Sinja, loyal to Otah and training up soldiers to help defend the Khaiem against the Galts, who stumbles into the midst of the Galt army, not realising their full intentions, and is forced to play the role of hired mercenary and traitor to his people in order to survive.
Abraham manages to create his world superbly. Previously we have seen a great deal of the eastern-style Khaiem culture, with its teahouses, robes, elegant poses and soaring palaces, created by the power of the andat. Now for the first time we see the less impressive, but somehow more familiar, world of the Galt, with technology filling the andat-less void, and cities built on the smaller scale of human endeavour alone.
The book is even more of a page turner than the previous one was, as the Galts race to complete their plan before winter stalls them, and the Khaiem race to delay them as long as possible, so that the two remaining poets, Maati and Cehmai, have a chance to create an andat with the possibility of victory. The ending, when it comes, is both highly credible and yet searingly painful to read.