A knight is a person granted an honorary title of a knighthood by a head of state or representative for service to the monarch, the church, or the country, especially in a military capacity.
A 14th-century depiction of the 13th-century German knight Hartmann von Aue, from the Codex Manesse
A Norman knight slaying Harold Godwinson (Bayeux Tapestry, c. 1070). The rank of knight developed in the 12th century from the mounted warriors of the 10th and 11th centuries.
Hungarian knights routing Ottoman sipahi cavalry during the Battle of Mohács in 1526
David I of Scotland knighting a squire
Chivalry, or the chivalric language, is an informal and varying code of conduct that developed in France between 1170 and 1220. It is associated with the medieval Christian institution of knighthood,
Knight
…the High Middle Ages, knighthood was considered a class of petty nobility. By the Late Middle Ages, the rank had become associated with the ideals of chivalry, a code of conduct for the perfect courtly Christian warrior. Often, a knight was a vassal who served as an elite fighter or a bodyguard for a lord…
Konrad von Limpurg as a knight being armed by his lady in the Codex Manesse (early 14th century)
God Speed by English artist Edmund Leighton, 1900: depicting an armoured knight departing for war and leaving his beloved
Reconstruction of a Roman cavalryman (eques)
Knights of Christ by Jan van Eyck