I would say the Hittites and the Celts. The Hittites thrived and disbanded before the beginnings of the Roman empire. The Celts were absorbed by the Romans but were keen to follow their ways.
Answer:
I didn't know either so just ask other to do that
John locke
Voltaire
Adam Smith
Mary Wollstonecraft
If its the law it might be the selective training and service act.