Pope Leo X, Lord of Florence, reigned as Bishop of Rome and Sovereign of the Pontifical States from 1513 to 1521. Born Giovanni de'Medici, was a member of the Medici family that ruled Florence and Etruria. Cardinal de' Medici was elected to the papacy following Pope Saint Julius II. He oversaw the closing sessions of the Fifth Council of the Lateran and led a war that successfully secure his nephew's rule as Duke of Urbino. He was also a great patron of the arts, following the tradition of his family. Perhaps most famously, he issued the Bull Exsurge Domine that excommunicated Martin Luther, effectively launching the Counter-Reformation. As such, he is the first Baroque Roman Pope.