Two Spartan brothers, raised in different circumstances, come together in one of the battles of the Pelopennesian War. It's a good look at a strange culture. Most books of antiquity focus on the Athenians. This one is surprising.
Besides being a fascinating view of the Spartan culture, the three main characters are very skillfully portrayed.
The mother, brutally raped during a helot uprising, immediately picks herself up, tracks her assailant down and kills him. She manages to quickly find a husband and successfully passes off her illegitimate offspring as his get. Consequently, she has no love for any of her family and tolerates them only to enhance her social standing, despising her first born and favoring the legitimate son to his detriment. When she is a widowed, she soon becomes a cunningly successful entrepreneur.
Ironically, the hated older son develops all the Spartan virtues: self-reliance, loyalty, endurance in adversity, adherence to truth and virtues. His younger brother cheats and has no respect for laws, tradition or family.
When the two are sent as part of the scant force to defend the barren approach to a strategic harbor, their true natures eventually become known to some of their comrades.