The Medici continue their rise to power. In 1421, Papa Joe became gonfaloniere. Around the same time, Pope Marty finally appointed the Medici as the papal bankers. And Papa Joe retires and hands over control of the bank to his two sons – Cosimo and Lorenzo. Then in 1422, Florence gets involved in a costly war with Milan, which bankrupts the city and gives rise to the castato taxation system – a new way of taxing the rich.