The ideas of chivalry and courtly love are widely evident in the Middle Ages among the knights. It is modeled after the Arthurian legend in England that combines Christian virtues with military values. Chivalry is the code of conduct that knights upheld. Courtly love, on the other hand, is a romantic devotion to someone who is virtually unattainable.
Dante is definitely influenced by these two ideas in writing his Divine Comedy.
It is the predominant culture after all. Although not widely used throughout the poem, it is very evident in Dante's love for the unattainable Beatrice. It is moving him enormously throughout the poem. Poets during the medieval ages were able to elevate courtly love into something philosophical and more profound meaning for love.