Long has the question of truth been pondered. Long has this been a folly few recognise in time. A killer, a soldier even with a sword is one thing. But a killer who thinks he has found a definite truth, which he decides to fight for, is the most dangerous man in the world.
Surnames: The Chinese were among the very first cultures to adopt the use of hereditary surnames (around 2800 BC). But the custom didn't quite catch on in Europe - at least not until the Venetian aristocracy made it popular sometime between the 10th and 11th centuries AD. What culture made it popular in your setting and why?