Nudity in sculptures of the Italian Renaissance was directly related to the renewed interest in Classical learning that came about during the period. Throughout the Middle Ages, the Catholic church was the leading voice in art, literature, philosophy, morality, and culture in general (of course, I'm only speaking of the West here). They said that depictions of nudity in art were immoral (aside from certain specific circumstances, such as depictions of Adam and Eve prior to their expulsion from the garden of Eden). The Italian Renaissance is characterized as a rebirth of secular knowledge. Works of ancient philosophy were being studied by scholars and works of ancient art were being unearthed. Artists working during the Italian Renaissance began depicting subjects from Greek mythology, something that would have been highly unusual in the Middle Ages. They also began depicting religious subject matter in ancient styles, such as Michelangelo's David. Physical perfection was highly prized in ancient philosophy and art, so depictions of heroes were nearly always nude to showcase this trait. In their emulation of ancient subject matter and artistic styles, Italian Renaissance artists began depicting nudity in their sculpture.