Just found a book on how St. Francis transformed the ideal of chivalry from something worldly to something heavenly: Gospel Chivarly: Franciscan Romanticism by Father Mark Elvins.
This is from another post where I quote the good father:
In fact, the Franciscan way of life offered a corrective to excesses of military life. The ideal of chivalry promoted not only courage, honor and generosity, but also fidelity and courtesy. Unfortunately, knights often used their prowess and largesse in their own interests, abusing the poor and defenseless, whom they were duty bound to protect. Father Mark Elvins, writing in Second Spring, speaks eloquently on the way in which the charism of St. Francis purified the spirit of chivalry, indeed as Father Elvins puts it, that charism “inverted” or “reversed,” the values of chivalry:
By reversing the status of the knight, Francis found his new and spiritual knighthood, a chivalry suffused with the Gospel to replace the aristocratic propaganda of his age. This spiritual knighthood was not so much a system as a gradual discernment, as he viewed his hitherto privileged life in the light of faith, and sought to integrate it into the life of Christ, Celano describes how Francis consciously sought to exchange carnal weapons for spiritual ones, and worldly prowess for humbles service, making homage and fealty to the poor Christ, the King of Heaven (II Celano, 6) (“St. Francis and the Reversal of Chivalry,” Issue 2 – 2002. 22, 23).