Courtly Love, code of behavior that defined the relationship between aristocratic lovers in Western Europe during the Middle Ages. Influenced by contemporary chivalric ideals (see Chivalry) and feudalism, courtly love required adherence to certain rules elaborated in the songs of the troubadours (see Troubadours and Trouvères) between the 11th and the 13th centuries and stemming originally from the Ars Amatoria (The Art of Loving) of the Roman poet Ovid.

According to these conventions, a nobleman, usually a knight, in love with a married woman of equally high birth—or, often, higher rank—had to prove his devotion by heroic deeds and by amorous writings presented anonymously to his beloved. Once the lovers had pledged themselves to each other and consummated their passion, complete secrecy had to be maintained. Because most noble marriages in the Middle Ages were little more than business contracts, courtly love was a form of sanctioned adultery, sanctioned because it threatened neither the contract nor the religious sacrament of marriage. In fact, faithlessness of the lovers toward each other was considered more sinful than the adultery of this extramarital relationship.

Literature in the courtly love tradition includes such works as Lancelot, by Chrétien de Troyes; Tristan und Isolt (1210), by Gottfried von Strassburg; Le Roman de la Rose, by Guillaume de Lorris and Jean de Meun; and the Arthurian romances (see Arthurian Legend). The theme of courtly love was developed in Dante Alighieri's La vita nuova (The New Life) and La divina commedia (The Divine Comedy), and in the sonnets of the Italian poet Petrarch.