When he proved to be a good fighter

At a ceremony called dubbing, a squire was made into a knight. He was only made into a knight if he was a good fighter. At the dubbing the squire knelt in front of his lord. He would have his sword suspending from his neck. After that, he would promise that he would protect the weak, the church, and his lord. The sword that was placed in his scabbard is taped against his shoulder, and announced him knight

Knights relied in their land for everything

Almost all novels were Knights, but it had to be earned

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Dubbing