Medieval knights were the professional warrior class of Europe, responsible for defending their feudal lord's territory from rival lords and keeping the local serfdom in line with the lord's rule. Knights were frequently members of the noble class, with the title inherited through the father, but it was also a title granted as a reward for chivalrous deeds. In the late medieval period, noble and warrior classes became more static.
The primary role of a knight in medieval society was to fight battles for his lord, similar to that of the samurai of Japan. Knights were an elite class of warriors that specialized in armored combat from horseback and used weapons such as the longsword, lance, dagger and various blunt weapons. They conducted themselves according to the Code of Chivalry, which stressed courtly etiquette and valor in battle as well as devout Christian faith.
Not only did knights protect their lords from attack by other lords, but they also served as a military force for the king of the country should he require it. The king had the right to request all lords to offer a contingent of knights in defense of the land or in offensive actions such as the Crusades.