Devotio Moderna, or Modern Devotion, was a movement for religious reform, calling for apostolic renewal through the rediscovery of genuine pious practices such as humility, obedience and simplicity of life. It began in the late fourteenth-century, largely through the work of Gerard Groote, and flourished in the Low Countries and Germany in the fifteenth century, but came to an end with the Protestant Reformation. It is most known today through its influence on Thomas à Kempis, the author of The Imitation of Christ, a book which proved highly influential for centuries.