I used to have two rules: always read books by people named Sean and always try books by Australians US publishers went to the trouble of acquiring the rights. Like a lot of arbitrary filters, those worked until they failed catastrophically1 but I was well pleased with discovering Australian author Sean McMullen.
Lights up on a world much like Earth but with crucial differences and the siege of the city of Larmentel by the glorious imperial might of the armies of Emperor Warsovran. Unfortunately for Warsovran’s soldiers, their grand skills at siege-craft were learned from the scholars of Larmentel and the scholars kept their best tricks for themselves. Things are not going well but they are about to become much worse.