Leo X (1475-1521), who was pope from 1513 to 1521, was a lavish patron of the arts and an international political manipulator. The Reformation began during his reign.

In the second half of the 15th century the Renaissance was in full swing in Italy. The glories of man had been rediscovered and were being reappreciated after the religious austerities of the Middle Ages. The classic art of ancient Greece had come back into style; the ornate Latin of early Rome was being mastered again. Life in this world had become more important, for those who could afford it, than life in the next. The princes of Italy's city-states fought and schemed to preserve their power and increase their wealth.

It was into this kind of world that Giovanni de' Medici, the future pope Leo X, was born on Dec. 11, 1475. His father, Lorenzo de' Medici or Lorenzo the Magnificent, ruled Florence...