The House of Medici was a political dynasty in Italy from Tuscany which ruled over the Duchy of Florence from 1531 to 1737. Pope Leo X, Pope Clement VII, and Pope Leo XI were from the Medici family, as were Queens of France Catherine de Medici and Marie de Medici. The family began to gain influence under Cosimo de Medici, who was the lord of Florence from 1434 to 1464, and the Medici Bank was one of the most prosperous and respected institutions in Europe (it may have been the wealthiest family in Europe at one time). The Medici family ended when Gian Gastone de Medici died in 1737 without children, ending 300 years of Medici rule over Tuscany.