Chivalry, or the chivalric code, is an informal and varying code of conduct developed in Europe between 1170 and 1220. It was associated with the medieval Christian institution of knighthood; knights' and gentlemen's behaviours were governed by chivalrous social codes. The ideals of chivalry were popularized in medieval literature, particularly the literary cycles known as the Matter of France, relating to the legendary companions of Charlemagne and his men-at-arms, the paladins, and the Matter of Britain, informed by Geoffrey of Monmouth's Historia Regum Britanniae, written in the 1130s, which popularized the legend of King Arthur and his knights of the Round Table. All of these were taken as historically accurate until the beginnings of modern scholarship in the 19th century.

The code of chivalry that developed in medieval Europe had its roots in earlier centuries. It arose in the Carolingian Empire from the idealisation of the cavalryman—involving military bravery, individual training, and service to others—especially in Francia, among horse soldiers in Charlemagne's cavalry. The term "chivalry" derives from the Old French term chevalerie, which can be translated as "horse soldiery". Originally, the term referred only to horse-mounted men, from the French word for horse, cheval, but later it became associated with knightly ideals.

Over time, its meaning in Europe has been refined to emphasize more general social and moral virtues. The code of chivalry, as it stood by the Late Middle Ages, was a moral system which combined a warrior ethos, knightly piety, and courtly manners, all combining to establish a notion of honour and nobility.