Final answer:
Chivalry is the code that said all knights had to be brave in battle and is now the basis of good manners in most Western societies.
Step-by-step explanation:
The code that said all knights had to be brave in battle and is now the basis of good manners in most Western societies is called chivalry. Chivalry was a code of ideal conduct that aimed to validate the practices of noble warriors by Christianizing knightly violence and behavior. It emphasized values such as protecting the church, women, and the defenseless, observing truces, and not fighting on religiously significant days.