The French Revolution was an inevitable event in human history. Feudalism was being replaced by Capitalism; caused by the emerging bourgeoisie's class struggle against the nobility. Focused upon the Enlightenment movement as a cause of the Revolution. Doyle blamed structures of society rather than the Enlightenment.
Technological advancements
While the Spartans were known for being strong in battle after the battle has ended the king actually send his trumpeters back and send his army to retrieve the dead. When the enemies wanted to retrieve the dead as well they would send over a representative to negotiate.