You often see many paintings from the Renaissance as Nude paintings. Many Nude paintings are a direct result of the artist of the time’s experimentation. The artists tried to understand perspective and realistic forms. They were also trying to understand and map the human body on all its forms.

Most artists of the Neoclassicism found beauty in the idealized thoughts and artworks of ancient Romans and Greeks and wanted to recreate this.

Nude paintings came to the forefront in the Renaissance largely because the unclothed human figure represents a timeless ideal of humanity. That, at least, was the overarching rationale.

There were also great advances made in anatomical science at the time, so the understanding of how the body works mechanically was better understood and celebrated.

Once you get past these high-minded reasons, the final reason is that patrons, in other words people who buy paintings, are just like other people: They like to look at nudes; especially beautifully done nudes.