Middle Ages
In the 13th century mendicant orders—the Franciscans and the Dominicans—who swore vows of poverty and earned their living by begging, were approved by the papacy. Religious groups such as the Waldensians and the Humiliati also attempted to return to the life of early Christianity in the middle 12th and early 13th centuries, but they were condemned as heretical by the papacy. Others joined the Cathars, another heretical movement condemned by the papacy. In 1209, a crusade was preached against the Cathars, the Albigensian Crusade, which in combination with the medieval Inquisition, eliminated them.

Q: What notable vow was sworn by the mendicant orders?
poverty