What Makes a Samurai?

The normans had amazing energy for 200 years. They settled in normandy, quickly forgot that part of the deal that said were vassals of you. But what it meant was they were fighting and rabble rousing,. conquering places as far apart as england, continental france, italy., playing a major role on the first crusade. And eventually, what ends of happening to them as they get absorbed into all these societies that they were involved in?